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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Acta diabetologica 9 (1972), S. 655-687 
    ISSN: 1432-5233
    Keywords: Chinese hamster ; Diabetes ; Glycogen infiltration ; Kidney ; Nuclear glycogenosis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Cette enquête sur l'ultra-structure du rein de hamsters chinois atteints de diabète a permis de relever des lésions glomérulaires légères, consistant en un épaississement non-homogène des membranes basales des vaisseux capillaires, des altérations de cellules de la mésange, une dilatation irrégulière des anses vasculaires. Sur la partie tubulaire, une accumulation de glycogène dans le cytoplasme des cellules de la partie distale et du tube collecteur ainsi que la présence de glycogène dans le noyau des animaux atteints d'un grave diabète et de kétose.
    Abstract: Resumen La presente investigación sobre la ultraestructura del riñón del hamster chino diabético, ha dado la posibilidad de poner en evidencia sutiles lesiones glomerulares, consistentes en el engrosamiento no homogéneo de las membranas basales de los vasos capilares, en alteraciones de las células del mesangio, en la dilatación irregular de las ansas; y, a cargo de la parte tubular, en una acumulación de glicógeno en el citoplasma de las células del tramo distal y del túbulo colector y en la presencia de glicógeno en el núcleo de los animales con diabetes grave y quetosis.
    Notes: Riassunto La presente indagine sulla ultrastruttura del rene di hamsters cinesi diabetici ha fatto rilevare fini lesioni glomerulari, consistenti in ispessimento non omogeneo delle membrane basali dei vasi capillari, alterazioni delle cellule del mesangio, dilatazione irregolare delle anse vascolari. A carico della parte tubulare, accumulo di glicogeno nel citoplasma delle cellule del tratto distale e del tubulo collettore; presenza di glicogeno nel nucleo negli animali con diabete grave e chetosi.
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  • 2
    ISSN: 1432-5233
    Keywords: Cyclophosphamide treatment ; Guinea pig ; Experimental diabetes ; Immunodiabetes ; Immunosuppression ; Insulin resistance ; Islets of Langerhans ; Precipitating insulin antibodies ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Hyperglycémie, amélioration de la tolérance à l'insuline et modifications considérables à niveau des cellules B et A des ilots de Langerhans ont fait l'objet d'une observation, après immunisation par insuline et adjuvant, en cobayes produisant des anticorps anti-insuline précipitants. Le traitement par le cyclophosphamide inhibait la production d'anticorps anti-insuline, alors que la glycémie et la tolérance à l'insuline restaient aux mêmes niveaux qu'on pouvait vérifier chez les animaux de contrôle non immunisés. Même les îlots de Langerhans semblaient avoir subi des dommages moins importants par rapport à ceux des animaux qui n'avaient pas été traités par le cyclophosphamide.
    Abstract: Resumen En covayos productores de anticuerpos antinsulina precipitantes, tras inmunización con insulina y adyuvante, se ha podido observar: hiperglicemia, aumento de la tolerancia a la insulina y conspícuas modificaciones a cargo de las células A y B de las islas de Langerhans. El tratamiento con ciclofosfamida inhibía la producción de anticuerpos antinsulina, mientras la glucemia y la tolerancia insulínica permanecían en los mismos niveles que podían observarse en los animales de control no inmunizados. Las islas de Langerhans aparecían menos dañadas respecto a las de los animales no tratados con ciclofosfamida.
    Notes: Riassunto Iperglicemia, aumento della tolleranza all'insulina e cospicue modificazioni a carico delle cellule B ed A delle isole di Langerhans sono stati osservati, dopo immunizzazione con insulina in adiuvante, in cavie produttrici di anticorpi anti-insulina precipitanti. Il trattamento con ciclofosfamide inibiva la produzione di anticorpi anti-insulina, mentre la glicemia e la tolleranza insulinica rimanevano agli stessi livelli riscontrabili negli animali di controllo non immunizzati. Anche le isole di Langerhans apparivano meno danneggiate rispetto a quelle degli animali non trattati con ciclofosfamide.
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  • 3
    ISSN: 1432-2013
    Keywords: Diphosphate ; Rat ; Vitamin D Metabolism ; Intestinal Calcium ; Absorption ; Bone Mineralization ; Renal Functions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The metabolism and the organ distribution of double labelled vitamin D3 (1,2-3H-4-14C-cholecalciferol) has been studied in rats in which the bone mineralization and the intestinal calcium absorption have been inhibited by a large pose (10 mg P/kg s.c. for 7–14 days) of disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP). The most striking difference found was a reduced accumulation of radioactive cholecalciferol and its metabolites in the kidney of EHDP-treated rats. It is unlikely that this effect was due to an unspecific alteration of the functional renal tissue since blood urea, glomerular filtration rate and renal plasm a flow remained unaltered by this dose of EHDP. The EHDP-treated rats were able to form the metabolite eluted with peak IV of the silicic acid chromatographic system, that is 25-hydroxycholecalciferol. In these vitamin D repleted rats fed a high calcium diet, the tritium deficient metabolite eluted with peak V (1,25-dihydroxycholecalciferol) was only found in the intestinal mucosa of both control and EHDP groups three days after the injection of radioactive cholecalciferol, and this in a very small amount. Therefore no definitive conclusion can be drawn as to a possible interference of EHDP treatment on the production of 1,25-dihydroxycholecalciferol. The change in the renal metabolism of vitamin D in rats treated with a rachitogenic dose of EHDP may be caused by the modifications of the calcium metabolism brought about by the diphosphonate. Its relation, if any, with the decreased calcium absorption remains to be established.
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 272 (1972), S. 369-377 
    ISSN: 1432-1912
    Keywords: Trimethoprim ; Placental Transfer ; Distribution ; Elimination ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary After a single i.v. administration of 50 mg/kg of Trimethoprim (TM) to rats in late pregnancy, a diffusion equilibrium of the folic acid inhibitor in the foetal organs is reached after 30–60 min. The TM levels in maternal as well as in foetal organs can have an inhibitory effect on folic acid reductase activity. The elimination of TM is lower in pregnant than in non-pregnant animals. The TM elimination of the foeti is dependent on the elimination capacity of the mother. Three-days-old rats eliminate TM some four times slower than mature animals owing to their reduced kidney development.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 272 (1972), S. 417-436 
    ISSN: 1432-1912
    Keywords: Intestinal Blood Flow ; Instestinal Absorption ; Tritiated Water-Solvent Drag ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Jejunal loops of anaesthetized rats were perfused with hypo-, iso-, and hypertonic buffered solutions containing tritiated water. The blood flow, the disapperance rate (from the intestinal lumen), and the appearance rate (in the intestinal venous blood) were determined simultaneously. 2. A decrease of the blood flow from about 1.7 to 0.2 ml min−1g−1 wet tissue weight diminished the appearance and disappearance rate of tritiated water. An increase of the blood flow caused the reversed results. The appearance rate was almost completely determined by the blood flow indicating that the intestinal absorption of tritiated water is blood flow limited. Therefore the absorption rate of tritiated water characterizes badly the diffusive water permeability of the intestinal epithelium. 3. A water net flux directed towards the blood accelerated and towards the intestinal lumen retarded the intestinal absorption of tritiated water at low, intermediate, and high blood flow values. 4. The data were analysed by a modified four-compartment-model considering the variation of blood flow and water net flux. The water net flux influences the absorption of tritiated water during the penetration through the epithelium by solvent drag (sieving coefficient 1-σ=1.54±0.19) as well as by changing the blood flow rate through capillaries near the epithelium.
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 274 (1972), S. 357-374 
    ISSN: 1432-1912
    Keywords: Intestinal Blood Flow ; Blood-to-Lumen Flux ; Tritiated Water ; Solvent Drag ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Anaesthetized rats were loaded with tritiated water and a jejunal loop was perfused with hypo-, iso-, and hypertonic buffered saline solutions. The blood flow, the disappearance rate (from the blood), and the appearance rate (in the intestinal lumen) were determined simultaneously. 2. A decrease of the blood flow from about 1.7 to 0.2 ml min−1g−1 wet tissue weight diminished both the appearance rate and the disappearance rate of tritiated water. An increase of the blood flow caused the reversed results; however, at high blood flow the appearance and disappearance rate did not reach the value measured in the experiments with decreasing blood flow. 3. A water net flux directed towards the blood retarded and towards the intestinal lumen accelerated the blood-to-lumen flux of tritiated water at low, intermediate, and high blood flow values. 4. The data were analysed by a modified four-compartment-model considering the variation of blood flow and water net flux. The water net flux influences the blood-to-lumen flux of tritiated water by solvent drag during the penetration through the epithelium and by changing the luminal concentration (e.g. dilution) as well as the blood flow rate in the capillaries near the epithelium.
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 273 (1972), S. 352-365 
    ISSN: 1432-1912
    Keywords: Calcium Transport ; Small Intestine ; Rat ; in vitro ; in vivo
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Intestinal calcium (Ca) transport was studied in the rat jejunum by the in vitro perfusion technique of Fisher and Parsons and in the tied loop in vivo. Mucosal uptake and absorption of Ca was examined under the following conditions: rising intraluminal Ca-concentrations (0.5–128 meq/l); inhibition of energy dependent metabolism (2,4-dinitrophenol, N2, low temperature); net water flow, out of or into the intestinal lumen; addition of strontium (Sr); pretreatment with low Ca-diet and with 6-methyl-prednisolone. The concentration-dependent Ca absorption curve rose steeply at low Ca-concentrations but changed to a slowly rising straight line above 16 meq/l Ca++. In contrast, Ca uptake into the intestinal wall was directly related to Ca concentration, was linear from the beginning and paralleled the straight part of the absorption curve. Ca absorption was decreased by inhibition of energy dependent metabolism, addition of Sr and pretreatment with prednisolone. Pretreatment with low Ca diet increased Ca absorption and direction of net water flow (“solvent drag”) had no effect on it. Mucosal uptake of Ca was similar to Ca absorption except that metabolic inhibition increased Ca uptake but decreased Ca absorption. These results are compatible with the concept of a passive mucosal uptake and of an active absorption of Ca at low intraluminal Ca concentrations with additional passive component at high Ca concentrations.
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Naunyn-Schmiedeberg's archives of pharmacology 274 (1972), S. 91-106 
    ISSN: 1432-1912
    Keywords: Choline ; Blood-Brain-Barrier ; Brain ; Rat ; Lecithin
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In the rat brain the concentration of choline increases with a velocity of 20.5 nMol/g×min immediately after decapitation. This is not due to postmortal disintegration of the tissue but to persisting biochemical reactions in the absence of blood flow. This rise of choline must be considered if the concentration of choline in the living animal is to be established. Taking this fact into account one arrives at a value of 27.5±1.7 nMol Choline/g wet weight. From the arterio-venous difference of choline concentrations it has been postulated that there is an efflux of 7.2±1.5 nMol/g×min from the brain into the blood. After i.v. injection of labelled choline the peak of the specific radioactivity of choline in the brain is reached in less than 1 min but amounts to only one tenth of the specific activity of choline in blood-plasma. The specific activities in both compartments decline in parallel. Thus it can be concluded a) that choline penetrates easily through the blood-brain barrier, but the concentration gradient is directed from brain to blood; and b) that choline is continuously formed in the brain, which process permanently dilutes the quantity of labelled choline and prevents the specific activities in blood and brain from becoming equal. The calculations of turnover-rates in the different reactions leading to the choline containing glycerophosphatides are based on the data obtained. On the basis of these findings it is proposed that in the brain phosphorylated derivatives of ethanolamine (phosphorylethanolamine, cytidinediphosphate-ethanolamine) can be methylated to form the respective choline derivatives.
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Journal of cancer research and clinical oncology 77 (1972), S. 279-291 
    ISSN: 1432-1335
    Keywords: Lung mouse tumors ; Chemical carcinogen ; Ultrastructure ; Pneumocyte II ; Crystalline inclusions ; Interstitial fibrosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary The pulmonary tumours induced in Swiss mice by NMUR seem to be constituted for the most part by cells closely related to the granular pneumocytes (pneumocytes II ou B). Other rarer cells, of epithelial bronchiolar aspect, may take part in the proliferation. The ultrastructural study of tumoral cells suggest that their secretory functions are disturbed. The origin of the crystalline intratumoral structures is discussed, as well as their possible relationship with the production of surfactant. The peritumoral areas are characterized by a dense interstitial flbrosis in which the collagen fibers are associated with an elastoid substance.
    Notes: Resumé Les tumeurs pulmonaires induites chez la souris swiss par le NMUR apparaissent essentiellement constituées de cellules apparentées aux pneumocytes granuleux (pneumocytes II ou B). D'autres cellules plus rares, de morphologie épithéliale bronchiolaire peuvent participer á la prolifération. L'étude ultrastructurale des cellules tumorales suggère que leurs fonctions secrétoires sont perturbées. Le mode de formation des structures cristallins intratumorales est discuté, ainsi que leur rapport éventuel avec la production du surfactant. Les territoires péri-tumoraux sont caractérisés par une fibrose interstitielle dense où les fibres de collagène sont associées à uns substance élastoïde.
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 10 (1972), S. 238-251 
    ISSN: 1432-0827
    Keywords: Growth ; Bone ; Rat ; Tetracycline
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La vitesse de croissance normale en longueur de la métaphyse proximale du tibia est déterminée chez le rat Sprague-Dawley entre les âges de 20 et 100 jours, en utilisant la méthode à la tétracycline. Le taux de croissance ne varie que légèrement dans les groupes d'âges différents. Il est plus élevé chez les animaux jeunes et décroit considérablement en fonction de l'augmentation de l'âge. Les rats mâles présentent une croissance plus élevée que les femelles. Cette étude a pour but de mettre au point une méthode permettant de déterminer les facteurs expérimentaux, liés à la croissance en longueur du rat.
    Abstract: Zusammenfassung Die normale Längenwachstums-Geschwindigkeit der proximalen Wachstumsplatte der Tibia wurde bei Sprague-Dawley-Ratten in einem Alter zwischen 20 und 100 Tagen mittels der Tetracyclinmethode gemessen. Die Wachstumsgeschwindigkeit variierte nur wenig innerhalb der einzelnen Altersgruppen. Die Geschwindigkeit war bei jungen Tieren am höchsten und nahm mit zunehmendem Alter beträchtlich ab. Männliche Ratten wuchsen schneller als weibliche. Diese Arbeit dient als Grundlage, um die experimentelle Beeinflussung des Längenwachstums der Ratte abschätzen zu können.
    Notes: Abstract The rate of normal growth in length from the proximal growth plate of the tibia in the Sprague-Dawley rat was measured between 20 and 100 days of age using the tetracycline method. The growth rate varied only slightly within different age groups. The rate was highest in young animals and decreased considerably with increasing age. Male rats grew faster than female. This study is intended to provide a base for an evaluation of experimental influence on the growth in length of the rat.
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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 9 (1972), S. 238-242 
    ISSN: 1432-0827
    Keywords: Dentine ; Ultrastructure ; Tubule ; Tooth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé L'étude ultrastructurale de la dentine humaine périphérique, de couronnes dentaires de sujets âgés de 11 à 75 ans, a montré trois aspects principaux du contenu des canalicules en coupe transversale. Il s'agit de canalicules apparemment vides, de canalicules contenant un matériel organique annulaire et, enfin, de canalicules totalement remplis d'un matériel organique d'aspect granulaire ou hyalin. Aucune terminaison nerveuse n'est visible à ce niveau.
    Abstract: Zusammenfassung Die ultrastrukturelle Untersuchung von peripherem menschlichem Zahnkronendentin bei Patienten im Alter von 11–75 Jahren hat drei Hauptaspekte des Inhaltes der Dentintubuli gezeigt. Sie bestehen bei transversalen Schnitten aus toten Gängen sowie beim Lumen der Tubuli entweder aus ringförmigen oder ganzausfüllenden Ablagerungen. Im äußeren Dentin wurden keine Nervenendigungen beobachtet.
    Notes: Abstract An ultrastructural study of peripheral human coronal dentin in patients aged 11 to 75 years, has shown main aspects of the dentinal tubular content. In transverse sections, they consist of dead tracts and annular or solid content to the tubular lumen. No nerve endings were observed in the outer dentin.
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  • 12
    Electronic Resource
    Electronic Resource
    Springer
    Archives of toxicology 30 (1972), S. 29-38 
    ISSN: 1432-0738
    Keywords: Dichlorvos ; Teratology ; Inhalation ; Rat ; Rabbit ; Dichlorvos ; Teratologie ; Inhalation ; Ratte ; Kaninchen
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An Kaninchen und Ratten wurde die teratogene Wirkung von inhaliertem Dichlorvos untersucht. Im Versuch waren primipare Kaninchenweibchen der Rasse “Dutch” mit einem Anfangsgewicht von 2 bis 3 kg und primipare Rattenweibchen vom Stamm “Carworth Farm E“ mit einem Anfangsgewicht von 200 bis 300 g. Die Tiere wurden während der gesamten Trächtigkeit folgenden Konzentrationen in der Atemluft ausgesetzt: 0,25, 1,25 und 6,25 μg Dichlorvos pro Liter Luft. Ein zusätzliches Experiment am Kaninchen wurde mit 2 und 4 μg Dichlorvos pro Liter Luft durchgeführt. Die Behandlung wirkte weder beim Kaninchen noch bei der Ratte teratogen. Selbst Konzentrationen, die für die Kaninchen tödlich waren, und die eine deutliche Cholinesterasehemmung in Plasma, Erythrocyten und Gehirn der Ratten und Kaninchen hervorriefen, wurden ohne Schädigung für die Feten vertragen.
    Notes: Abstract The teratogenic potential of inhaled dichlorvos vapour for rabbits and rats was investigated on the offspring of primiparous female Dutch rabbits weighing 2 to 3 kg and primiparous female Carworth E strain rats weighing 200 to 300 g. The animals were exposed throughout pregnancy at concentrations of 0.25, 1.25 and 6.25 μg dichlorvos per litre of air. In an additional experiment pregnant rabbits were exposed to concentrations of 2 and 4 μg dichlorvos per litre of air. The results gave no indication that dichlorvos vapour is teratogenic in rabbits or rats even at exposure concentrations resulting in maternal deaths in rabbits, and causing depression of plasma, erythrocyte and brain cholinesterase activities in pregnant animals of both species.
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  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Archives of toxicology 30 (1972), S. 9-18 
    ISSN: 1432-0738
    Keywords: 2,2-Dichlorvinyl Dimethyl Phosphate ; Dichlorvos ; Vapona ; Metabolism ; Man ; Rat ; Mouse ; Hamster ; 2,2-Dichlorvinyl-dimethylphosphat ; Dichlorvos ; Vapona® ; Stoffwechsel ; Mensch ; Ratte ; Maus ; Hamster
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung An Mäusen und Hamstern wurde die Exkretion und Retention der Radioaktivität nach Fütterung mit [1-14C-Vinyl]-Dichlorvos bestimmt. Außerdem wurde beim Menschen die Exkretion und Exhalation gemessen und die erhaltenen Werte mit den tierexperimentellen Daten von Rattenversuchen verglichen. Die Ergebnisse zeigen einen schnellen Stoffwechsel von Dichlorvos bei allen vier untersuchten Species. Die Dealkylierung zu Desmethyldichlorvos spielt bei der Biotransformation eine untergeordnete Rolle. Eine gewisse Ausnahme zeigen die Mäuse, bei denen 18,5 % der zugeführten Radioaktivität als Desmethyldichlorvos aufgefunden werden konnte. Bei allen Species kam es zu einer hydrolytischen Spaltung zu Dichloracetaldehyd, der weiter zu Dichloraetbanol reduziert wird. Der weitere Weg führt über die Ausscheidung als Glucuronid mit dem Harn. Ein Teil wird dechloriert und das14C-Atom als14CO2 oder14C-Hippursäure im Harn ausgeschieden. Im menschlichen Harn konnte Dichloraethanol nach Inkubation mitβ-Glucuronidase nachgewiesen werden, wenn hohe Dichlorvoskonzentrationen (38 μg/l) eingeatmet wurden. Auf dieser Basis könnte eine Überwachungsmethode gegen die Inhalation von zu hohen Dichlorvoskonzentrationen ausgearbeitet werden.
    Notes: Abstract The routes of excretion and retention of radioactivity following the ingestion of [1-14C-vinyl]dichlorvos by mice and hamsters have been determined. The excretion of radioactivity in urine and exhaled air of man has also been measured. The data have been compared with those for rats. The results indicate that metabolism is rapid in the four species. Dealkylation to desmethyldichlorvos is a minor route of biotransformation, except in the mouse, where desmethyldichlorvos constitutes at least 18.5 % of the administered radioactivity. Hydrolytic metabolism of dichlorvos occurs in all species and leads presumably to dichloroacetaldehyde which is further metabolized by (i) reduction to dichloroethanol and excretion in the urine as the glucuronide and (ii) dechlorination followed by incorporation of the carbon atoms into endogenous biosyntheses and excretion as [14C]carbon dioxide and [14C]hippuric acid in the urine. Dichloroethanol can be detected inβ-glucuronidase-treated urine after exposure of a human subject to high air concentrations (38 μg/l) of non-radioactive dichlorvos. This may form the basis of a method of monitoring the exposure of humans to high concentrations of dichlorvos.
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  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Archives of toxicology 28 (1972), S. 39-45 
    ISSN: 1432-0738
    Keywords: Ferrihexacyanoferrate (II) ; Rat ; Thallium ; Toxicity ; Metabolism ; Ferrihexacyanoferrat(II) ; Ratte ; Thllium ; Toxicität ; Stoffwechsel
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die Verabfolgung einer 2% igen kolloidalen Lösung von Ferrihexacyanoferrat (II) (FHCF) als Trinkwasser erhöht bei der Ratte die Ausscheidungsrate von intravenös injiziertem Tl2SO4 (mit 204Tl markiert) aus Leber, Nieren und Muskulatur auf das 2,8fache. Dieser Effekt ist zeitunabhängig. Die LD 50/30 d von intravenös injiziertem Tl2SO4 wird durch FHCF-Behandlung um das 2,3fache erhöht. Für diesen Schutzeffekt ist allerdings nur das während der ersten 24 Std verabfolgte FHCF verantwortlich. Diese Befunde weisen darauf hin, daß die Schäden bei der akuten Tl-Intoxikation sehr schnell irreversibel werden.
    Notes: Abstract The administration of a 2% colloidal solution of ferrihexacyano ferrate (II) (FHCF) as drinking water increases in the rat the excretion of intravenously injected Tl2SO4 (labelled by 204Tl) from liver, kidneys and muscles by a factor of 2.8. This effect is independant of time. FHCF-treatment increases the LD 50/30 d of intravenously injected Tl2SO4 by a factor of 2.3. This protection, however, is provided by FHCF only if administered during the first 24 hours. These findings suggest that the damage resulting from acute Tl-intoxication quickly becomes irreversible.
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  • 15
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 9 (1972), S. 296-309 
    ISSN: 1432-0827
    Keywords: Osteoclasts ; Enzyme ; Parathyroid ; Microdissection ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé Une nouvelle méthode d'isolement d'ostéoclastes est mise au point pour des analyses biochimiques et de microscopie électronique. Pour isoler les cellules par microdissection, des empreintes d'os métaphysaire sont utilisées. Cette méthode, supérieure aux coupes d'os, permet une meilleure préservation cytologique et enzymatique et permet d'obtenir des cellules totales plus faciles à manipuler, avec des résultats plus reproductibles. Par analyse planimètrique de cellules isolées, colorées histochimiquement, il apparait que les ostéoclastes constituent plus de 90% de la masse de l'échantillon. Les concentrations de la phosphatase acide et de certaines enzymes, liées au nucléotide pyridinique, entrant dans le métabolisme de l'acide citrique, sont déterminées dans des échantillons d'ostéoclastes, pesant de 0,2 à 2,0 μg, isolés à partir de rats normaux et parathyroidectomisés. L'activité en aconitase, mesurée en direction de la transformation de citrate en isocitrate, est de 0,5–0,8 M/Kd/H, la plus faible des activités étudiées. Les activités en GDH et NADP-ICDH sont 5 à 10 fois supérieures que celle de l'aconitase, mais seulement un dixième à un tiers de celle de la phosphatase acide, de la déshydrogénase lactique ou malique.
    Abstract: Zusammenfassung Es wird eine neue Technik beschrieben, welche die Isolierung von Osteoklasten für biochemische und elektronenmikroskopische Untersuchungen ermöglicht. Als Ausgangsmaterial zur Zellisolierung wurden Abstriche von Metaphysenknochen benützt. Die Verwendung von Abstrichen bietet gegenüber Knochenschnitten wichtige Vorteile, wie z.B. eine bessere Erhaltung der cytologischen und enzymatischen Eigenschaften sowie die Gewinnung von unverletzten Zellen, welche leichter verarbeitet werden können und besser reproduzierbare Daten ergeben. Durch planimetrische Analyse der histochemisch gefärbten Ausstriche von isolierten Zellen konnte nachgewiesen werden, daß die Osteoklasten über 90% des gesamten Probenmaterials ausmachen. Die Mengen verschiedener Enzyme, welche an Pyridinnukleotid gebunden und am Citronensäuremetabolismus beteiligt sind, sowie der sauren Phosphatase wurden in Osteoklastenproben bestimmt, welche ein Gewicht von 0,2–2,0 μg hatten und aus Knochen von normalen und mit Parathyroidextrakten behandelten Ratten isoliert worden waren. Die Aktivität der Aconitase, welche in der Richtung von Citrat zu Isocitrat gemessen wurde, war mit 0,5–0,8 M/Kd/H die niedrigste aller untersuchten Aktivitäten. Die Aktivitäten der GDH und der NADP-ICDH waren 5–10mal höher als jene der Aconitase, entsprachen jedoch nur einem Zehntel bis einem Drittel derjenigen der sauren Phosphatase, der Laktat- oder der Malatdehydrogenase.
    Notes: Abstract A new method is described by which osteoclasts can be isolated for biochemical and electron microscopic analyses. As a source of cells for isolation by microdissection, imprints of metaphyseal bone were used. The use of imprints provides important advantages over bone sections, including a higher degree of cytologic and enzymatic preservation, and the delivery of whole cells which are more readily manipulated and which yield data that are more readily reproduced. By planimetric analysis of the histochemically-stained isolated cell samples, it was shown that osteoclasts represent over 90% of the sample mass. The levels of several of the pyridine nucleotide-linked enzymes involved in citric acid metabolism, as well as acid phosphatase, were determined in osteoclast samples weighing 0.2 to 2.0 μg isolated from normal and parathyroid-treated rats. Aconitase activity measured in the direction of citrate to isocitrate was 0.5–0.8 M/Kd/H, the lowest of the activities studied. The activities of GDH and NADP-ICDH were 5 to 10 times higher than that of aconitase but only a tenth to a third that of acid phosphatase, lactic or malic dehydrogenase.
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  • 16
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    Anatomy and embryology 137 (1972), S. 106-113 
    ISSN: 1432-0568
    Keywords: Anterior pituitary ; Mouse ; Tissue culture ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Suitability of an ordinary incubation system for the culture of anterior pituitary tissues of mice was examined by electron microscopy. It was found that this system has many advantages over Trowell's standard technique for tissue culture and is particularly suitable for the short-term culture. In this system the pituitary tissue cultures were maintained well for at least two days in a chemically defined tissue culture medium (TC 199) without any additives. Addition of 20% calf serum to the medium extended the period to up to five days. Any attempts to prolong it further, however, failed because of a massive necrosis and a great loss of the histological integrity. In the cultured tissues there an enhancement of the LTH cells and a suppression of the other granulated types of cells were observed. The follicular cells were found to hypertrophy and to actively participate in phagocytosis of cell debris.
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  • 17
    ISSN: 1432-0568
    Keywords: Chick embryo ; Granular pneumocytes ; Granular inclusions ; Lamellar inclusions ; Ultrastructure ; Lung
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Les inclusions lamellaires caractéristiques des cellules granuleuses de l'épithélium pulmonaire apparaissent chez le Poulet à 16 jours d'incubation. Elles dérivent d'inclusions granulaires que l'on peut déceler dans l'épithélium dès l'apparition de l'ébauche pulmonaire, à 21/2 jours d'incubation. Nous avons étudié l'évolution de ces deux types d'inclusions lorsque les ébauches pulmonaires sont transplantées sur des hôtes d'âge différent. Lorsque une ébauche pulmonaire jeune (21/2 à 3 jours) est greffée sur un hôte plus âgé (6 jours), l'évolution des inclusions granulaires est fortement stimulée et peut conduire à l'apparition d'organites présentant plusieurs des caractères des inclusions lamellaires. Lorsqu'au contraire, une ébauche pulmonaire est transplantée sur un hôte plus jeune (3 jours), deux cas peuvent se présenter: Ou bien l'épithélium ne contient pas encore d'inclusions lamellaires au moment de la transplantation (ébauche de 14 jours par exemple): le moment d'apparition de celles-ci est alors considérablement retardé et leur différenciation ne devient massive que lorsque les inclusions lamellaires apparaissent dans le poumon de l'hôte; Ou bien les inclusions lamellaires sont déjà différenciées (poumon de 18 jours par exemple): dans ce cas, leur différenciation se poursuit pendant toute la durée de la greffe. Lorsqu'une ébauche pulmonaire est transplantée sur un hôte plus âgé ou plus jeune, l'évolution ultrastructurale de l'épithelium est donc modifiée. Selon les cas, elle est stimulée ou, au contraire, freinée. Des facteurs présents dans le milieu intérieur de l'hôte influencent la différenciation des greffons. Ils pourraient également intervenir dans de développement normal des poumons.
    Notes: Summary The lamellar inclusions of the granular pneumocytes first appear in chick pulmonary epithelium at 16 days of incubation. They are derived from granular inclusions which can already be seen in the epithelium at the time when lung buds become distinct (at 21/2 days incubation). We have studied the fate of these two types of organelles after transplantation of embryonic lungs to hosts of a different age. When a young lung bud (21/2 to 3 days) is grafted into an older host (6 days), the development of the granular inclusions is strongly stimulated, and can lead to the appearance of organelles which exhibit several features characteristic of lamellar inclusions. When an embryonic lung is transplanted to a younger host, two situations can occur: Either the epithelium does not yet contain any lamellar inclusions at the time of transplantation (eg lung at 14 days); these appear after a considerable delay, and differentiate in large quantities only at the time of appearance of the inclusions in the host lungs. Or the lamellar inclusions are already differenciated (eg lung at 18 days), in which case, their differentiation continues in the host. Therefore, when a lung bud is transplanted into either a younger or older host, the ultrastructural development is modified. It is either stimulated or inhibited. Some factors, present in the host internal milieu, influence the differentiation of the grafts. These factors could also play a role in the normal development of the lungs.
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  • 18
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    Anatomy and embryology 137 (1972), S. 301-316 
    ISSN: 1432-0568
    Keywords: Monoamines ; Brain ; Ontogeny ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The early ontogeny of the monoamine neuron systems in the rat brain has been analysed using Falck-Hillarp fluorescence histochemistry. Serial sagittal sections of embryos with a crown rump length between 7 and 13 mm, approximately corresponding to gestational days 12 to 15 were obtained from mothers treated with a monoamine oxidase inhibitor given in order to increase the monoamine levels of the embryos. 5-hydroxytryptamine (5-HT)-neurons made their first appearance in the 8 mm embryo, dopamine (DA)-neurons in the 9 mm embryo, and noradrenaline (NA)-neurons in the 11 mm embryo. Small, rounded, weakly fluorescent cell bodies forming sparse aggregations appeared first. Fluorescent processes of two types soon appeared. Short processes from the cell bodies were running perpendicular to the long axis of the brain stem within the cell groups, while long slender axon bundles could be traced ascending through the met- and mesencephalon and into the prosencephalon as well as descending in the myelencephalon andspinal cord. In the 12 mm embryo the primordial DA cell formation of the substantia nigra with its striatal projections, the 5-HT neuron formations of the caudal mesencephalon, met- and myelencephalon as well as the NA neurons of the met- and myelencephalon are relatively well developed. It is concluded that the monoamine-neurons develop mechanisms for synthesis and storage of amines at a very early stage during ontogeny, thus recapitulating the phylogeny of these old systems. Likewise, monoamine oxidase is present early. The presence of neurotransmitters specifying the different developing neurons long before development of their nerve terminal areas and therefore before the establishment of normal synaptic function may indicate a role of these substances during ontogeny other than transmission of nerve impulses.
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  • 19
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    Anatomy and embryology 137 (1972), S. 153-169 
    ISSN: 1432-0568
    Keywords: Embryology ; Epithelial autophagia ; Histocytochemistry ; Human palate ; Macrophages ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary An ultrastructural and a histochemical study of the disintegration of the human fetal palatinal junctional epithelium was carried out. Special attention was focused both on the epithelium proper as well as on participation of the surrounding mesenchyma. Epithelial autophagia was noticed in the form of inclusion bodies with cellular remnants as well as general cellular disintegration. The disintegration was correlated to the cellular activity of acid phosphatase and AS-esterase. The differences between human and non-human material were recorded and discussed. In the surrounding mesenchyma, histiocytes (macrophages) were noticed participating in the epithelial disintegration, while ordinary mesenchymal cells seemed without importance. The study of activity of alkaline phosphatase reveals that the rapidly growing ossification center of the vomer was touching the superior aspect of the epithelial junctional seams, where the epithelial disintegration starts. Based upon the findings the following sequential steps of disintegration were discussed: 1) pressure from the outside (the vomer anlage), 2) epithelial autophagia and 3) heterophagia of epithelial remnants (invading histiocytes). The ultrastructure and histochemistry of the so-called epithelial pearls were described. The intercellular substance of the palatinal processes was found to consist of hyaluronic acid and of chondroitin-4- and/or-6-sulfate. The mutual ratio of the glycosaminoglucuronoglycans was discussed.
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  • 20
    ISSN: 1432-0568
    Keywords: Rat ; Cold ; Pineal gland ; Synaptic vesicles ; Zinc iodide-osmium tetroxide (ZIO) reaction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In den synaptischen Bläschen der Nervenendigungen der Epiphyse von Ratten, welche 2 und 4 Tage einer Temperatur von −6° bis −8°C ausgesetzt worden waren, hat man eine signifikante Vermehrung des Zinkjodid-Osmiumtetroxyd (ZIO) reaktiven Materials festgestellt. Der durchschnittliche Durchmesser der ZIO-positiven synaptischen Vesiculae betrug bei den Kontrollratten 234 Å und bei den Ratten, welche 2 und 4 Tage unter der Kälte gelebt hatten, 380 Å, bzw. 379 Å. Die ZIO-Reaktion war bei den Kontrollratten in 49,3% der synaptischen Vesiculae positiv, nach zweitägiger Kälteeinwirkung waren 58,7% und nach viertägiger Kälteeinwirkung 72,1% der synaptischen Vesiculae ZIO-positiv. Auf Grund der vorliegenden Arbeit war es jedoch nicht möglich zu entscheiden, ob die Vermehrung des ZIO-reaktiven Materials mit einer gleichzeitigen Zunahme der biogenen Amine verbunden ist.
    Notes: Summary In the synaptic vesicles of pineal nerve endings of Wistar rats exposed for 2 and 4 days to a temperature of −6° to −8° C, a significant increase of the zinc iodide-osmium tetroxide (ZIO) reactive material was observed. The mean diameter of ZIO reactive synaptic vesicles of control rats was 234 Å; in rats exposed to cold for 2 and 4 days it was 380 Å, respectively 379 Å. In control rats the ZIO reaction was positive in 49,3% of the synaptic vesicles. The reactivity increased to 58,7% in rats exposed to cold for 2 days, and to 72,1% in rats exposed to cold for 4 days. However, the results of the present study do not permit to conclude if an increase of ZIO reactive material is accompanied by a simultaneuos increase of biogenic amines.
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  • 21
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    Anatomy and embryology 137 (1972), S. 1-29 
    ISSN: 1432-0568
    Keywords: Corticotropin-Releasing Factor ; Median eminence ; Rat ; Histology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In der Zona externa infundibuli der normalen Ratte kommen geringe Mengen „Gomori-positiver” Granula vor. Nach bilateraler Adrenalektomie erfolgt eine Vermehrung der Granula, die sich durch Gabe von Hydrocortison einschränken oder verhindern läßt. Dieser Befund hat zu der Annahme geführt, daß die Granula das morphologische Äquivalent des Corticotropin-releasing factor (CRF) darstellen. Morphometrische Untersuchungen an 160 weiblichen Wistarratten zeigen, daß die Menge der nach bilateraler Adrenalektomie in der Zona externa infundibuli nachweisbaren „Gomori-positive” Granula von der postoperative Überlebensdauer abhängt. Die Granulamenge nimmt zunächst bis zum 14. Tag p.o. zu und fällt dann wieder ab. Substitution bilateral adrenalektomierter Ratten mit Hydrocortisonacetat-Kristallsuspension bewirkt eine dosisabhängige Verminderung der Granulamenge, wenn die Behandlung am Operationstag begonnen wird. Applikation von Hydrocortisonacetat-Kristallsuspension vom 14.–21. Tag p.o. führt dagegen zu einer gesteigerten Granulavermehrung. Auch bei stärkster Vermehrung sind die Granula stets nur im Infundibulum und nicht in anderen Bereichen des Hypothalamus nachweisbar. Sie besitzen bei bilateral adrenalektomierten Tieren ein charakteristisches Verteilungsmuster mit besonders hohen Konzentrationen in den paramedianen Abschnitten des rostralen Infundibulumdrittels. Aus der Art und Weise ihrer Verteilung ist zu vermuten, daß die Granula 2 Nervenfaserzügen angehören und ein Neurosekret darstellen. Nach den vorliegenden Untersuchungen besteht zwischen dem Verhalten der „Gomori-positiven” Granula in der Zona externa infundibuli und dem aus pharmakologischen Untersuchungen bekannten Verhalten des Corticotropin-releasing factor eine weitgehende Parallelität. Sie legt nahe, die Menge der Granula als Parameter der CRF-Aktivität zu verwenden.
    Notes: Summary In the zona externa infundibuli (outer layer of the median eminence) of the normal rat a minute number of “Gomori-positive” granules can be detected. Following bilateral adrenalectomy their number increases. This augmentation can be restricted or inhibited by administration of hydrocortisone, a finding, which has led to the assumption that the granules are the morphological equivalent of the corticotropin-releasing factor (CRF). Morphometrical studies on 160 female Wistar rats show that following bilateral adrenalectomy the quantity of “Gomori-positive” granules is dependent on the length of the post-operative survival period. Up to the 14th day p.o. the quantity of granules increases; from then on it diminishes. Substitution of bilaterally adrenalectomized rats with hydrocortisone acetate crystal suspension results in a dose-dependent decrease in the quantity of granules if treatment is begun on the day of operation. In contrast, administration of hydrocortisone acetate crystal suspension from the 14th to the 21st day p.o. results in increased augmentation of the granules. Even when maximum augmentation of the granules is reached, they are invariably found only in the infundibulum and not in other regions of the hypothalamus. In animals that have been subjected to bilateral adrenalectomy, the granules show a characteristic pattern of distribution, with particularly high concentrations in the paramedian parts of the rostral third of the infundibulum. The manner in which the granules are distributed suggests that they are a neurosecretory substance localized in two fibre tracts. The present study points to a close parallelism between the behaviour of the “Gomori-positive” granules in the zona externa infundibuli and that of the corticotropin-releasing factor as revealed by pharmacological investigations. It would seem that the quantity of granules can be used as a parameter of CRF activity.
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  • 22
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    Anatomy and embryology 138 (1972), S. 155-165 
    ISSN: 1432-0568
    Keywords: Cerebellum ; Neurogenesis ; Autoradiography ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Time of origin of various neuronal elements in the cerebellum of rat was established with the aid of tritiated-thymidine-autoradiography. The earliest nerve cells to form were the Purkinje cells, and they came into existence on days 15 and 16 of gestation. Interstitial nerve cells had their genesis on days 15, 16, 17 and 18, and the marginal cells on day 16 of the embryonic development. The Golgi cells were found to come into existence on days 17, 18 and 19 of gestation. On day 21 of gestation a number of small-medium-sized nerve cells, which were smaller than the Golgi cells but larger than the granule cells, were seen to come into existence. Finally, the earliest stock of granule, basket and stellate cells, primarily in the nodulus, flocculus and para-flocculus, were observed to have been formed on the day 21 of embryogenesis.
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  • 23
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    Acta neuropathologica 21 (1972), S. 109-116 
    ISSN: 1432-0533
    Keywords: Infantile Neuro-Axonal Dystrophy ; Motor End Plates ; Nerve ; Spheroïds ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The authors report the ultrastructure of neuromuscular biopsies in three cases of infantile neuro-axonal dystrophy. The presence of spheroïds in peripheral and intramuscular nerves, but also in the motor end plates allows the diagnostic of this disease, without doing cerebral biopsy.
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  • 24
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    Acta neuropathologica 21 (1972), S. 68-75 
    ISSN: 1432-0533
    Keywords: Myelinated Nerve ; Venom ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The fine structure of right sciatic nerves of Swiss white mice was studied after being exposed to a venom solution ofAgkistrodon contortrix laticinctus (broad-banded copperhead) and to 0.9% NaCl solutions for periods of 1, 2 or 3 h. There was some “Wallerian-like” degeneration in all groups of nerves in the experiment. Additional neuropathological changes were noted in the nerves exposed to venom solutions. The connective tissue was affected most severely, while the basal lamina was unaffected. Schwann cells were vacuolated, and in the most extreme case, a type of myelin splitting occurred which was considered as a “demyelinative” effect. The results were compared to those of Martin and Rosenberg (1968) [15] on studies of the giant squid axon. References to additional fine structural studies of various other neuropathies were given.
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  • 25
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    Acta neuropathologica 21 (1972), S. 239-252 
    ISSN: 1432-0533
    Keywords: Ultrastructure ; Myotendon ; Zebra-Bodies (ladder-like structure) ; Rods
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The ultrastructure of the adult and foetal human myotendon is described. At the myotendon the muscle fibre is surrounded by plasma and basement membranes which are never penetrated by the adjacent collagen fibrils of the tendon. Increased thickness and electron density of the plasma membrane and the myofilaments which merge with it occur at the myotendon and this electron dense zone corresponds to the terminal Z-line of the final sarcomere of the myofibril. In the adult the muscle fibre near the myotendon may contain nemaline rods and zebra-bodies. The tendon in the foetus shows much more activity of the fibroblasts than in the normal adult. The collagen fibrils of the early foetus are thinner in diameter than at later stages of development. The union of the tendon with cartilage is illustrated.
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  • 26
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    Acta neuropathologica 21 (1972), S. 253-257 
    ISSN: 1432-0533
    Keywords: Haemangiopericytoma, Cerebral-Secondary ; Histology ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A secondary haemangiopericytoma of the cerebral hemisphere in a woman of 23 is described. It is formed of cells arranged in masses around proliferating blood capillaries, and also in rosette patterns. The tumour cells are separated from the capillary endothelial cells by thick collars of basement membrane in abnormal amounts. The histology of the primary tumour of the sacrum, and of the secondary tumours in the lungs and nervous system, are similar. A metastatic haemangiopericytoma of the central nervous system appears not to have been previously reported.
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  • 27
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    Calcified tissue international 10 (1972), S. 38-48 
    ISSN: 1432-0827
    Keywords: Bivalve ; Molluse ; Shell ; Carbonates ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La technique du bombardement à l'aide d'ion d'argon est utilisée pour réduire l'épaisseur de la coquille de carbonate de calcium des bivalvesMytilus etMercenaria pour examen au microscope électronique par transmission et en diffraction électronique; une comparaison est réalisée à l'aide de répliques simples, servant de témoins. Les résultats obtenus confirment les études antérieures de répliques et de microscopie par balayage. De plus, une structure “aérée” est mise en évidence dans la coquille des aragonites, et surtout dans le nacre deMytilus. Cette structure est interprêtée comme un artefact induit par la chaleur, formé par l'inclusion d'eau et de matériel organique, interprétation qui concorde avec les études chimiques et de microscopie électronique.
    Abstract: Zusammenfassung Die Beschießung mit Argonionen wurde angewendet, um die Dicke von Calciumcarbonat-Schalen der zweischaligen MuschelnMytilus undMercenaria zu reduzieren. Diese Technik erlaubte die Ausführung von Transmissions-Elektronenmikroskopie und Elektronendiffraktion, wobei gleiche Proben nach einer bereits bestehenden Methode vorbereitet und als Kontrollen herangezogen wurden. Es wurden zusätzliche Resultate zu den Muschelstruktur-studien erhalten, welche früher publizierte Arbeiten unterstützen, die mit der Abklatschmethode und der Raster-Elektronenmikroskopie ausgeführt worden waren. Zusätzlich wurde eine „schaumartige” Struktur der Muschelaragoniten, besonders im Perlmutter vonMytilus, beobachtet. Da es sich um ein durch Hitze verursachtes Artefakt handelt, wird diese Struktur als Einschlüsse von Wasser und organischem Material interpretiert, was den Befunden von verschiedenen veröffentlichten chemischen und elektronenmikroskopischen Arbeiten entspricht.
    Notes: Abstract Use is made of the argon ion-bombardment technique to reduce the thickness of calcium carbonate shells of the bivalvesMytilus andMercenaria for transmission electron microscopy and electron diffraction, with comparison of single-stage replicas of similar specimens serving as controls. As an additional approach to shell structure studies, it gives results which support earlier published work with both replicas and scanning microscopy. In addition, a “frothy” structure is detected in the shell aragonites, especially inMytilus nacre. As a heat-induced artifact, it is interpreted as representing trapped water and organic material inclusions, an interpretation consistent with several published chemical and electron microscope studies.
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  • 28
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    Calcified tissue international 10 (1972), S. 216-222 
    ISSN: 1432-0827
    Keywords: Ultrastructure ; Callus ; Osteoclast ; Endocytosis ; Lysosomes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La bordure en brosse des ostéoclastes de cals de fractures de rats présente des plissements complexes de la membrane cytoplasmique formant des canaux étroits. L'absorption d'un produit exogène opaque aux électrons (des macromolécules de dioxyde de thorium) s'effectue par l'intermédiaire de ces canaux, par un «courant» membranaire. Les contenus des canaux sont transférés à des lysosomes («granules spécifiques»), situés sous la bordure en brosse. Dans des «régions de transition», adjacentes à cette dernière, l'absorption de dioxyde de thorium se fait par «vésiculation membranaire» (endocytose classique).
    Abstract: Zusammenfassung Der gekrauste Rand der Osteoklasten im Frakturcallus von Ratten besteht aus komplexen Einstülpungen der Plasmamembran, die enge Kanälchen bildet. Die Absorption einer exogenen, elektronisch dichten Verbindung, Thoriumdioxyd, erfolgt durch diese Kanäle, offenbar durch einen „Membranfluß”. Der Inhalt der Kanäle wird zu den Lysosomen („spezifische Granula”) geführt, welche unter dem gekrausten Rand liegen. In „Übergangsgebieten”, welche sich neben dem gekrausten Rand befinden, scheint die Aufnahme der Thoriumdioxydpartikel durch „Bläschenbildung in der Membran” (konventionelle Endocytose) stattzufinden.
    Notes: Abstract The ruffled border of osteoclasts in the fracture callus of rat consists of complex infoldings of the plasma membrane forming narrow channels. Absorption of an exogenous, electron-dense compound, thorium dioxide, has been shown to take place via these channels, apparently through “membrane flow”. The contents of the channels are transferred to lysosomes (“specific granules”) located subjacent to the ruffled border. In “transitional regions” adjacent to the ruffled border, uptake of thorium dioxide particles appeared to occur through “membrane vesiculation” (conventional endocytosis).
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  • 29
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    Archives of toxicology 29 (1972), S. 39-49 
    ISSN: 1432-0738
    Keywords: Mouse ; Rat ; Brain ; Light-Dark-Programming ; Circadian ; Toxicity Rhythms ; Acetylcholine ; Pilocarpine ; Oxotremorine ; Carbachol ; Physostigmine ; Neostigmine ; Atropine ; Scopolamine ; Atropine Methyl Nitrate ; Maus ; Ratten ; Gehirn ; Beleuchtungsprogramm ; Circadianer Toxicitätsrhythmus ; Acetylcholin ; Piloearpin ; Oxotremorin ; Carbachol ; Physostigmin ; Neostigmin ; Atropin ; Scopolamin ; Atropin-methylnitrat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Nach Adaptation an ein Licht-Dunkelprogramm (8.00 bis 20.00 Licht, 20.00 bis 8.00 Dunkelheit) wurde der Acetylcholingehalt (ACh) im Mittelhirn und N. caudatus von Ratten sowie im Gesamthirn von Mäusen bestimmt. Die höchsten ACh-Konzentrationen wurden bei Ratten um 24.00 gefunden; die höchsten ACh-Werte bei der Maus waren nicht signifikant von den Konzentrationen um 24.00 und 12.00 verschieden. Signifikante ACh-Minima traten im Mittelhirn der Ratte um 12.00, im N. caudatus sowie im Mäusegehirn um 18.00 Uhr auf. Während der Dunkelperiode wurde die größte Toxicität gegenüber i.v. bzw. i.p. injiziertem ACh bei Mäusen gefunden. Ähnliche zeitliche Unterschiede ergaben sich für Neostigmin, Pilocarpin und Oxytremorin. Die Toxicität von Carbachol zeigte Maxima bei 12.00 und 24.00. Für Physostigmin, einen CholinesteraseHemmstoff mit einem tertiären Stickstoff, lagen sowohl die Toxicitätsmaxima als auch die Toxicitätsminima in der Dunkelperiode. Die rhythmische Schwankung der Toxicität von i.p. verabfolgtem Atropin verhielt sich umgekehrt wie die der Cholinomimetica (außer Carbachol). Auch nach i.v. Applikation von Scopolamin und N-Methylatropin war ein entsprechender rhythmischer Einfluß auf die Toxicität nachweisbar. Die Vorbehandlung mit N-Methylatropin schwächte die Toxicität zwar ab, der Toxicitätsrhythmus gegenüber ACh und Physostigmin war aber nicht verändert. Die Toxicität von Cholinomimetica zeigt ein Maximum während der höchsten ACh-Konzentrationen im Gehirn und der höchsten Stoffwechselaktivität. Bei den anticholinergen Substanzen zeigte sich ein umgekehrtes Verhältnis. Die Beziehungen zum zentralen ACh-Gehalt sind unklar.
    Notes: Abstract Acetylcholine (ACh) levels were determined in rat midbrain and caudate nucleus and mouse whole brain in mature animals adapted 3 weeks to a programmed lighting schedule (08:00 to 20:00 h light; 20:00 to 08:00 dark). Peak ACh levels in the rat occurred at 24:00 h; in the mouse the peak at 06:00 h did not differ significantly from values obtained at 24:00 and 12:00 h. Significant trough values occurred at 12:00 h in rat midbrain and at 18:00h in rat caudate nucleus and mouse brain. In mice toxicity of I.V. and I.P. administered ACh is maximal during the dark. Neostigmine, pilocarpine and oxotremorine have toxicity patterns similar to ACh. Carbachol toxicity peaked at 12:00 and 24:00 h. With physostigmine, a tertiary anticholinesterase, peak and trough occurred during the dark. The atropine (I.P.) toxicity rhythm is a mirror image of the cholinomimetic rhythm (except for carbachol). I.V. scopolamine and atropine methyl nitrate patterns resemble atropine's but are less clear-cut. Atropine methyl nitrate pretreatment reduced ACh and physostigmine toxicity but did not alter the overall pattern. Cholinomimetic toxicity and brain ACh patterns are similar, peaking when metabolic activity is maximal. An inverse relationship holds for the anticholinergic drugs. The relationship to central ACh is uncertain.
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  • 30
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    Experimental brain research 15 (1972), S. 29-38 
    ISSN: 1432-1106
    Keywords: Ventromedial hypothalamus ; Single units ; Spontaneous and stimulated activity ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The relationship between mean firing rate and activity pattern was studied in 177 neurons in the ventromedial hypothalamus of rats immobilized by Remyolan. Stationary epochs of spontaneous or stimulated activity containing at least 512 interspike intervals were analyzed with the LINC computer. The most frequently encountered interval histograms (IHs) were of the exponential (35%) or gamma 2 (25%) type. The IH shape remained unchanged even if the average firing rate was varied over a wide range (from 20/sec to 2/sec) by polarization through the recording microelectrode (2–5 nA, 1–10 min) or by intracarotid injection of glucose (0.1 ml, 10–25%). The coefficient of variation (CV = SD/ mean interval) was 1.03 for the spontaneous and 0.90 or 0.95 for the activity influenced by polarization or glucose, respectively. Since according to other studies sensory stimulation decreases CV by reorganization of the synaptic input, it is suggested that polarization and glucose affect predominantly the postsynaptic elements without significantly changing the presynaptic activity pattern.
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  • 31
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    Acta neuropathologica 20 (1972), S. 248-257 
    ISSN: 1432-0533
    Keywords: Experimental CNS Tumours ; N-Nitrosomethylurea ; Ethylnitrosourea ; Cell Culture ; Clonal Growth ; Aggregation Pattern ; Transplantation ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Two sarcomas, one neurosarcoma and one polymorphous tumour of uncertain classification of the central nervous system of the rat induced by N-nitrosomethylurea or ethylnitrosourea were the source of 14 clones. The cytomorphology and the aggregation pattern of the clonesin vitro are described. The malignancy and histology were checked by homologous transplantation. All the clones formed sarcoma-like structuresin vivo, but it was difficult to decide whether these neoplasias were real sarcomas or very dedifferentiated glial tumours. The differences in cytology observedin vitro were greater than the histological differencesin vivo.
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  • 32
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    Acta neuropathologica 22 (1972), S. 269-271 
    ISSN: 1432-0533
    Keywords: l-DOPA ; Neoplasm, Striatal ; Motor Behavior ; Rat ; Catecholamines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary After administration ofl-DOPA to a rat with a unilateral striatal neoplasm of the nucleus caudatus-putamen, postural asymmetries and rotating behavior were observed. These observations are discussed in relation to the activity of catecholamines within the central nervous system.
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  • 33
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    Psychopharmacology 24 (1972), S. 449-455 
    ISSN: 1432-2072
    Keywords: Avoidance and Acquisition ; Methamphetamine ; Discrimination Learning ; CNS Stimulants ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Avoidance responses, extra responses (on avoidance lever) and wrong lever responses were measured in naive rats acquiring a discriminated avoidance in a 2 lever Skinner box, 30 min after methamphetamine (0.25, 0.5 and 1.0 mg/kg). The smallest dose was ineffective; 0.5 and 1.0 mg/kg significantly increased the number of avoidance responses. This increase was not associated with a significant increase in the two other responses studied. The progressive increase (from the first to second part of the acquisition session) in avoidance responses was not accompanied by a parallel increase in the other responses. The position discrimination and the discrimination of the presence or absence of the conditioned stimulus was observed to be better in the drug groups.
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  • 34
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    Psychopharmacology 26 (1972), S. 195-200 
    ISSN: 1432-2072
    Keywords: Forced Motility ; Motor Activity ; Brain Noradrenaline and 5-Hydroxytryptamine ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The levels of 5-HT and 5-HIAA in the rat brain were measured after 1, 6, 24 and 36 h of forced motility in a treadwheel. The results showed that 5-HT metabolism had already increased in the forebrain after 1 h of exercise but later also increased in the brain stem, especially in the mesencephalon-pons-medulla regions. These changes had almost entirely disappeared after 50 min of rest. The NA levels with and without monoamine oxidase inhibitor were measured in animals after 36 h of forced motility. The results indicated an increase in NA metabolism in the brain stem.
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  • 35
    ISSN: 1432-2072
    Keywords: Agressive Behaviour ; Apomorphine ; Testosterone ; Testes ; Hypophysis ; Adrenal Glands ; Thyroid ; Castration ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The weights of testes, prostates, adrenals, thymus and the pituitary of rats with apomorphine induced aggressiveness did not differ from those without aggressiveness. Postpubertal castration, adrenalectomy or thyroidectomy did not reduce the apomorphine induced aggressive behaviour, but a considerable reduction was found after hypophysectomy. Prepubertal castration significantly reduced, but did not completely abolish the proportion of aggressive rats, especially when castration was performed on the 5th day. Prolonged treatment of male, female and castrated rats with high doses of testosterone from the time of weaning increased the proportion of aggressive animals. Less intensive treatment and treatment of adult rats were ineffective.
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  • 36
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    Psychopharmacology 26 (1972), S. 317-320 
    ISSN: 1432-2072
    Keywords: Oxazepam ; Conflict Behavior ; Rat ; Maze
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Rats were tested in a Lashley III maze, the floor of which was heated. The animals had to learn to negotiate it in order to gain access to the unheated goal box. In the early period of training the animals were able to find the goal box rapidly and without error. Their performance then deteriorated, in a particular way which strongly evoked a conflict behavior. This deterioration in performance was progressively reduced by oxazepam administration (8 mg/kg/day).
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  • 37
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    Psychopharmacology 25 (1972), S. 218-228 
    ISSN: 1432-2072
    Keywords: Fighting ; Delta-9-Tetrahydrocannabinol ; Chlordiazepoxide ; Fixed-Interval ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The frequency with which electric shock to the feet elicited fighting in five pairs of albino rats was not altered significantly by intraperitoneal injections of delta-9-tetrahydrocannabinol (THC) in doses ranging from 0.064–6.4 mg/kg, although chlordiazepoxide reduced the frequency of such fighting in a dose-related manner. This finding held true despite manipulations of THC vehicle, injection-test interval, and the previous drug experience of the subjects. In contrast, doses of 4.0 mg/kg produced a striking reduction in lever-pressing maintained by an FI 60″ schedule of food reinforcement.
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  • 38
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    Psychopharmacology 23 (1972), S. 171-179 
    ISSN: 1432-2072
    Keywords: Reserpine ; Neonatal Treatment ; Sexual Behaviour ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To investigate whether reserpine given in the critical period of sexual differentiation of the rat brain affects adult sexual behaviour, female and male rats were given a single injection of reserpine on the fourth day after birth, and their sexual behaviour was tested at maturity. In the 11 consecutive daily tests for spontaneous sexual behaviour the reserpine treated female animals showed fewer regular behavioural and vaginal oestrous cycles than the control animals. 19 % of the reserpinized and none of the control animals had prolonged oestrous behaviour without a coincident prolonged vaginal cycle. The reseptivity quotients of the reserpine treated animals were reduced. In the tests for hormone induced sexual behaviour after ovariectomy no statistically significant differences between the number of animals responding or between the receptivity quotients occurred. The tests for spontaneous sexual behaviour in males showed that the reserpinized animals needed fewer intromissions to ejaculate than the controls. The significance of these findings is discussed.
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  • 39
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    Psychopharmacology 26 (1972), S. 347-360 
    ISSN: 1432-2072
    Keywords: Chronic Nicotine ; Attention Task ; Arousal ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Male, Holtzman rats were trained extensively on an attention task which required them to respond with a single lever-press to a very short, variably presented stimulus for food reinforcement, but which also required them to inhibit inappropriate responses. After performance had stabilized, two groups were treated with either nicotine base (100 Μg/kg, s.c., t.i.d.) or saline for 4 weeks. The groups were crossed-over so that the first received saline and the second nicotine for an additional 4 weeks. A 3-week saline recovery period followed. Rats were tested on the attention task daily through all periods. Analysis of the data indicated that independent of the treatment-order, rats performed more efficiently under nicotine treatment than under saline conditions. The improvement in performance was most notable in the reduction of inappropriate responding during chronic nicotine treatment. The significance of the behavioral changes in relation to proposed nicotine-induced neurophysiological changes and the two-arousal hypothesis are discussed.
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  • 40
    ISSN: 1432-2013
    Keywords: Cardiac Output ; Blood O2 Dissociation Curve ; High Altitude ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In rats adapted to a simulated altitude of 3500 m cardiac output measured at hypoxia by the direct Fick principle was significantly lower than in the control animals (mean values 54.3 ml/min and 69.8 ml/min, resp.). The decrease of cardiac output was accompanied by an increase of arterio-venous O2 difference and a decrease of stroke volume in the adapted rats. It is suggested that the decrease of cardiac output might be related to the increase of hematocrit. The adapted rats also showed higher arterial and mixed-venous O2 content (both at hypoxia) and increased O2 capacity. Arterial O2 saturation of the animals previously exposed to simulated high altitude hypoxia was significantly higher (67.3% as against 61.2% in the controls). The standard O2 dissociation curve showed lower oxygen affinity in the blood of the adapted animals but no physiological advantage concerning the transport of O2 to the tissues was found. In another group of animals the Bohr factor was estimated and no difference was found between rat and human blood.
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  • 41
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    Pflügers Archiv 335 (1972), S. 198-212 
    ISSN: 1432-2013
    Keywords: Intestinal Absorption ; Medium Chain Fatty Acids ; Kinetics ; Active Transport ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. The transport of14C-octanoate by rat small intestine was determined in vitro by a modification of the method of Semenza and Mühlhaupt, and in vivo by using isolated segments or a perfusion technique in conscious rats (Haberichet al., 1968). 2. The absorption capacity of14C-octanoate in the distal ileum was significantly lower than in the proximal jejunum. 3. 14C-octanoate injected into a jejunal segment appeared rapidly in portal venous blood reaching its maximal concentration 4 min after the injection. 4. The transport of octanoate showed a saturation effect with increasing concentrations after an incubation of 4 min. However, with constant concentrations of octanoate in the medium, the transport rate was constant for 8–10 min. A similar saturation effect was also demonstrated in vivo. Values for maximal absorption rate (V max) and the half-saturation constant (K m), calculated from the Lineweaver-Burk plot, were 1.0 μMol/min and 17.7 mM, respectively. 5. Accumulation of octanoate in tissue water was demonstrated. For example, after incubation for 40 min in a medium concentration of 0.1 mM, the tissue/ medium ratio was 2.75:1. 6. Cyanide (2×10−4 M) markedly diminished the absorption rate of octanoate. 7. The absorption of octanoate was competitively inhibited by caproic acid (C6) in vitro. The inhibition constant (K i), calculated from the Dixon plot, was 47 mM. 8. Simultaneous administration of glucose and octanoate in vivo did not affect the absorption rate of the fatty acid. 9. These results suggest that the intestinal absorption of octanoate is an energy-dependant active process.
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  • 42
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    Pflügers Archiv 334 (1972), S. 293-302 
    ISSN: 1432-2013
    Keywords: Lactate Turnover ; l-Lactate14C (U) ; Hypoxaemia ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary 1. Lactate turnover was measured in 24 anesthetized rats using14C-U-(l) Lactate with the priming dose-infusion technique. 2. 14C Lactate in blood was determined with a specific radio-enzymatic micromethod. 3. Lactate turnover increases with blood lactate concentration in the range 0.5 to 3 mM. In a steady state system this relationship means that a new equilibrium may be achieved at a higher pool level, between lactate production and utilization. 4. Comparing available data in four mammalian species lactate turnover at normal lactate levels was found to be approximately constant when computed on a body surface unit basis.
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  • 43
    ISSN: 1432-2013
    Keywords: Cardiac Hypertrophy ; Diffusion Distance ; High Altitude ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In growing rats adapted to a simulated altitude of 3500 m for about 4 weeks and in their controls the evolution of cardiac ventricular weight was followed. The increase of total ventricular weight found in the adapted animals can be attributed exclusively to the increase of right ventricular weight. In other adapted and control animals cardiac capillary densities, muscle fiber diameter and external capillary radius were estimated and fiber—capillary ratio and diffusion distance were calculated. There was an increase of capillary density together with a decrease of muscle fiber density, fiber-capillary ratio and diffusion distance in the right but not in the left ventricle of the adapted rats. The muscle fiber diameters, however, were larger in both heart ventricles of the rats exposed to a simulated high altitude, especially in the right ventricle. This indicates that true hypertrophy of the muscle fibers is mainly responsible for the increase of right ventricular weight. In the left ventricle, however, a hypertrophy of the muscle fibers together with a decrease of stroma components is demonstrated. The physiological importance of the shorter diffusion distance in the right ventricle of the high altitude adapted rats is discussed and it is suggested that the shorter diffusion distance may help to keep the tissue O2 partial pressure above the critical value, mainly also in extreme situations with high myocardial O2 consumption.
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  • 44
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    Pflügers Archiv 331 (1972), S. 357-364 
    ISSN: 1432-2013
    Keywords: Thoracic Aorta ; Complex Dynamic Young's Modulus ; Age ; Serum Lipids ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In 2 groups of male albino rats (wistar-strain), 6 months and 18 months of age, dynamic Young's moduli in longitudinal direction were measured, at 5 different frequencies between 1 and 5 Hz. Each group consisted of 10 animals. Measurements were made at the natural length and at 1.2 times this length. From each animal several serum lipids were determined. It was found that: 1. measured at the natural length and 1.2 times this length, no significant difference of dynamic Young's moduli between both age groups could be demonstrated 2. concerning the dynamic Young's moduli there is significant interaction between stretch level and age 3. retraction was significantly smaller in the old rats than in the young ones 4. the old animals had a significantly higher serum lipid content than the young rats 5. no correlation between serum lipids and Young's moduli could be demonstrated.
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  • 45
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    Pflügers Archiv 337 (1972), S. 71-79 
    ISSN: 1432-2013
    Keywords: Rat ; Hypothalamus ; Prolactin ; LH
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Plasma levels of prolactin and LH were measured by radioimmunoassay following electrochemical stimulation of the medial preoptic area (MPO) or the arcuate nucleus (Arc.N.) in pentobarbital anesthetized proestrous rats. Differences in the secretion pattern of prolactin and LH were observed when stimulated by means of acutely or chronically implanted electrodes. Acute implantation and stimulation of the MPO resulted in no change in serum prolactin levels, whereas stimulation by means of chronically implanted electrodes evoked a marked increase in serum prolactin. The general observation was that electrostimulation in the acute experiments causes a less sharp but more prolonged prolactin and LH release from pituitary than stimulation through chronically implanted electrodes.
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  • 46
    ISSN: 1432-2013
    Keywords: Pulmonary Diffusing Capacity ; Alveolar-arterial O2 Pressure Difference ; High Altitude ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Steady-state pulmonary diffusing capacity for CO and alveolar-arterial O2 pressure differences were measured at hypoxia in growing rats adapted to a simulated altitude of 3500 m. The pulmonary diffusing capacity was significantly higher and the alveolar-arterial gradients were significantly lower in the adapted animals as compared with the controls exposed to hypoxia for the first time. The increased diffusing capacity could be explained entirely by the increase of blood O2 and CO capacity whereas the decrease of gradients might be explained by the increase of blood O2 capacity together with an increase of the arterio-venous O2 difference.
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  • 47
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    Journal of neurology 202 (1972), S. 21-36 
    ISSN: 1432-1459
    Keywords: Hydrocephalus, Experimental ; Ethylnitrosourea ; Experimental Hydrocephalus ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung 25 mg/kg Äthylnitrosoharnstoff wurden am 9 1/2. Tag der Schwangerschaft SD-JCL-Ratten injiziert. Die Feten wurden am Termin excidiert und mit dem Stereomikroskop untersucht. 78% der Feten zeigten einen Hydrocephalus. Die histologische Untersuchung in Stufenschnitten des Gehirns zeigte eine Stenose des Aquädukts ohne subependymale Gliose, ödematöse Plexus chorioidei mit prallgefüllten Gefäßen, spärlichem Bindegewebe und geschwollenen Epithelzellen, Verdünnung der telencephalen Wandungen mit schwach entwickelter granulärer Schicht und in der ependymalen Zone verbleibenden Neuroblasten. Die Entwicklung der jungen Ratten wurde studiert. 75% der neugeborenen Ratten zeigten klinisch gewisse Hinweise auf den Hydrocephalus. Stark betroffene Tiere wurden zunehmend somnolent und/oder gelähmt und starben meist vor Ende der 4. Woche. Der Eiweißgehalt des Liquors war nennenswert vermehrt. Es wurden subdurale, subarachnoidale und intraventrikuläre Blutungen beobachtet und als wahrscheinliche Todesursache angesehen. Die histologische Untersuchung der hydrocephalen Jungtiere ergab eine Abflachung der Ependymzellschicht und pralle Füllung corticaler Gefäße von der 2. Woche an. In späteren Stadien wurde eine Dickenabnahme der periventrikulären weißen Substanz, im besonderen im Bereiche des Occipitalhornes nachgewiesen. Im verdünnten Pallium waren Vacuolenbildungen des perineuralen Gewebes zu sehen, Verbreiterung der Virchow-Robinschen Räume und eine dem Status spongiosus ähnliche Degeneration. Verschiedene Formen ependymaler Wucherung wurden gesehen. Die vorliegende Studie stellt die erste postnatale Beobachtung von transplacentar verursachtem kongenitalem Hydrocephalus in der Ratte dar. Die hier beschriebene Technik erwies sich als einfaches und reproduzierbares Mittel, um einen kongenitalen Hydrocephalus in der Ratte zu erzeugen.
    Notes: Summary SD-JCL rats were injected with 25 mg/kg of ethylnitrosourea on day 9 1/2 of gestation. Fetuses were excised near term and examined under dissecting microscope. 78% of viable fetuses were found to be hydrocephalic. On the histologic study of the serial sections of the brain, a stenosis of the Sylvian aqueduct without subependymal gliosis, edematous choroid plexus with engorged vessels, scanty connective tissue and swollen epithelium, thinning of the telencephalic wall with poorly developed granular layers and the neuroblasts remaining in the ependymal zone, were the characteristic findings in the hydrocephalic fetuses. The natural course of the treated young rats was studied. 75% of the newborn rats showed some clinical evidence of hydrocephalus. Severely affected rats became progressively lethargic and/or paralytic, and died usually before the end of 4th week. Protein content of the cerebrospinal fluid was significantly increased. Subdural, subarachnoid and intraventricular hemorrhages were observed and suspected to be the cause of death. On the histological examination of hydrocephalic youngs, flattening of the ependymal cells and engorgement of the cortical vessels were observed as early as in 2-week-old youngs. In more advanced stages, there was noted the thinning of the periventricular white matter, especially around the occipital horn. The thin pallium showed vacuolization of the perineural tissue, enlargement of the Virchow-Robin space and the status spongiosus-like degeneration. Various types of ependymal proliferation was seen. The present study represents the first postnatal observation of the transplacentally induced congenital hydrocephalus in the rat. The present technique proved to be a simple and reproducible model of producing a congenital hydrocephalus in the rat.
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    Research in experimental medicine 159 (1972), S. 114-123 
    ISSN: 1433-8580
    Keywords: Scalds ; Local cooling ; Rat ; Quantity of leucocytes ; Verbrühung ; Lokale Kühlung ; Ratte ; Verhalten der Leukocyten
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Untersuchungen an Ratten ergaben folgende Befunde: 1. Sofortige lokale Kühlung nach der Verbrühung beeinflußt bei der Ratte im untersuchten Zeitraum von 15 Tagen den Verlauf der Erkrankung gemessen am Parameter der Leukocytenzahl. 2. Die Kühlungszeit muß ausreichend lang sein. 3. Die Kühlung muß früh genug einsetzen, beim Versuchstier Ratte innerhalb 5 min nach Verbrühung. 4. Bei verspätetem Kühlungsbeginn läßt sich auch durch Verlängerung der Kühlungsdauer das Verhalten der Leukocytenzahl im Ablauf des Krankheitsgeschehens nach Verbrühung nicht beeinflussen.
    Notes: Summary Following results are obtained in experiments with rats: Immediate local cooling after scald had a significant influence on progress of “burn-disease”. Time for local cooling must be long enough, onset of local cooling early enough. It is not possible to restore the consequences of a late onset by prolongation of cooling.
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  • 49
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    Research in experimental medicine 159 (1972), S. 87-98 
    ISSN: 1433-8580
    Keywords: Ultrastructure ; Small lymphocytes ; Throracic duct lymph ; Man
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Die charakteristische Feinstruktur der durch Drainage des Ductus thoracicus des Menschen gewonnenen Lymphocyten wurde beschrieben, ihre Größe und Kern-Plasma-Relation durch planimetrische Verfahren ermittelt. Zwei morphologisch unterschiedliche Formen kleiner Lymphocyten konnten beschrieben werden: Zellen, die durch einen chromatinarmen Kern und relativ lockeres Cytoplasma gekennzeichnet sind, das zahlreiche Zellorganellen (Golgifeld, Centriolen, Mitochondrien und freie diffus verteilte Ribosomen) einschließt, sowie Zellen mit chromatinreichen Kern und dichtem Cytoplasma mit auffallend wenig Mitochondrien, jedoch relativ zahlreichen freien Ribosomen. Eine mögliche funktionelle Bedeutung dieser beiden morphologisch unterschiedlichen kleinen Lymphocyten wird diskutiert. Danach werden die Zellen der ersten Gruppe als differenzierte Zellformen, die der zweiten jedoch als immunologisch aktivere kleine Lymphocyten angesehen.
    Notes: Summary The ultrastructure of small lymphocytes of human thoracic duct lymph is described and planimetric studies of their size and nucleus-cytoplasm relationship are made. Two morphologically different small lymphocytes could be recognized; cells with a nucleus with little chromatin and a relatively light cytoplasm inclosing many organelles (Golgifield, Centriol, Mitochondria, Monoribosomes), cells with compact chromatin and dense cytoplasm including only a few mitochondria but many monoribosomes. The possible function of these morphological different small lymphocytes was discussed. The first group is a well differentiated cellform, the second one may contain more immonulogical active small lymphocytes.
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    Cell & tissue research 123 (1972), S. 356-368 
    ISSN: 1432-0878
    Keywords: Ependyma ; Brain ; Rat ; Glycogen-rich cells ; Electronmicroscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ependyma of the lateral ventricle of the rat brain was investigated at different ages from 20 days to adulthood. A particular cell type occurs in the external wall of the ventricle, where the proliferative subependymal layer is present. These cells found at all ages studied, are characterized by a high content of glycogen, and a structure different of typical ependymal cells. A large number of nerve endings is situated in close vicinity of these cells, either free in the ventricle lumen, or sometimes ensheathed in the cells. No synapse was found between these endings an the glycogen-rich cells. These glycogen-rich cells undergo several modifications with age: their glycogen content is reduced in the adult, and they acquire a few cilia and gliofilaments. It is suggested that they represent a transitory differentiation of the ependyma, functionally linked with the proliferative subependymal layer.
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  • 51
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    Cell & tissue research 123 (1972), S. 486-495 
    ISSN: 1432-0878
    Keywords: Pomatoceros triqueter ; Cytokinesis ; Surface folding ; New surface membrane ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The first cleavage division of Pomatoceros triqueter eggs is described. Time-lapse microcinematographic and electron microscopic studies revealed that, prior to division, the plasma membrane was folded into pleats. These were not present after division. This fact pointed to an unfolding of the plasma membrane which enabled it to cover the increased surface area resulting from cleavage. It is suggested that the pre-cleavage folds are derived from the membranes of the cortical granules, which continue releasing their contents into the perivitelline region following fertilization and first division. Filamentous material in the form of a band was present subjacent to the plasma membrane in the region of the furrow. The individual filaments of this band measure 5 to 7 nm in cross section, the dimensions being similar to those described for other kinds of dividing cells.
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  • 52
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    Cell & tissue research 124 (1972), S. 1-11 
    ISSN: 1432-0878
    Keywords: Spermiogenesis ; Rat ; Spermatids ; Manchette ; Microtubules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The manchette or caudal tube has been examined in Stage 14 rat spermatids. The microtubules of the caudal tube have been found to be partially sheathed by smooth endoplasmic reticulum which appears to be continuous with the outer nuclear membrane of the redundant nuclear envelope. The microtubules in caudal regions of the manchette have been noted to be interconnected by links of unusual size and morphology. It is suggested that the caudal tube consists at this stage of development of two structures, membrane and microtubules and that the links between the microtubules appear to play a role in the structural order noted in the position of the tubules of the manchette. The possible significance of these links in relation to motility is discussed.
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  • 53
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    Cell & tissue research 124 (1972), S. 39-43 
    ISSN: 1432-0878
    Keywords: Ruminal epithelium ; Zonulae occludentes ; Goat ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Pansenepithel besitzt in den tiefen Hornzellen, die an das Stratum granulosum grenzen, eine Barriere. Diese Barriere, die das Labyrinth der Interzellularräume gegen das Pansenlumen verschließt, ist mit Zonulae occludentes ausgestattet.
    Notes: Summary The deep horn cells of the goat ruminal epithelium, which border the stratum granulosum, form an important component of the epithelial barrier. This barrier of the intercellular labyrinth presents zonulae occludentes (tight junctions).
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  • 54
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    Cell & tissue research 124 (1972), S. 311-319 
    ISSN: 1432-0878
    Keywords: Median eminence ; Rat ; Neurovascular contacts ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the median eminence of the rat axons of the supraoptic-paraventricular-hypophyseal tract with elementary neurosecretory granules (150–200 mμ) traverse the internal zone. Terminals containing dense core vesicles 60–120 mμ in diameter end on the portal capillaries of the median eminence. A unique organisation of the primary portal capillaries is shown. Endothelial cells have many fenestrae. The pericapillary space has numerous extensions all of which represent a special zone around the endothelial tube. The fine structural organisation and function of the neurovascular contacts in the median eminence are discussed.
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  • 55
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    Cell & tissue research 124 (1972), S. 354-366 
    ISSN: 1432-0878
    Keywords: Hippocampal region ; Rat ; Monoamine oxidase ; Chemoarchitectonics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary 1. The distribution of monoamine oxidase (MAO) in the hippocampal region of the rat has been studied in cryostat sections with the tryptamine-tetrazolium method of Glenner et al. 2. The staining pattern was rather diffuse as compared with the distribution of MAO in the guinea pig and of other enzymes in the rat hippocampal region. 3. However, there were differences in enzyme activity between different areas and layers which could be correlated to some degree with results obtained with other methods, e.g., silver impregnation, catecholamines, and acetylcholinesterase.
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  • 56
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    Cell & tissue research 126 (1972), S. 157-181 
    ISSN: 1432-0878
    Keywords: Nerve degeneration ; Nerve regeneration ; Crayfish ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cut and crushed crayfish claw nerves were examined with the electron microscope at intervals up to 6 months after lesion. In sections 1 centimeter distal to the lesion there were no signs of degeneration among the giant motor axons even after many months. Swelling of glial wrappings was observed within 48 hours of nerve severance and was particularly notable in the innermost glial layer, the adaxonal layer. Golgi elements, rough endoplasmic reticulum, and mitochondria accumulated in the glia. These changes were perhaps indicative of a greater supportive role required by the severed axons. Regeneration from the proximal stumps of the giant axons began within one week and had proceeded across the lesion gap by 4 weeks. Axon sprouts appeared to travel toward the terminals within the glial sheaths of the distal giant axon segments. Before regeneration was complete, as determined by a simple behaviour test, the regenerating axons occupied increasing proportions of the sheath space. After regeneration was complete occasional degenerations were seen among the sprouts. These degenerations may have occurred in regenerating axons which had grown to the incorrect muscles. The original distal giant axons probably degenerated, as well, after regeneration was complete. There was no evidence of rehealing of proximal and distal segments of the axons.
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  • 57
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    Cell & tissue research 126 (1972), S. 320-334 
    ISSN: 1432-0878
    Keywords: Glandulae submaxillares ; Mammals ; Acinar cell granules ; Ultrastructure ; Histochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Granules in acinar cells show considerable variations in size, shape, electron-density and molecular organisation of secretory material. Discrete organelles with an electron-dense homogenous matrix are seen in the guinea-pig and to some extent in the male hamster. Similar organelles with moderate electron-density are seen in the cat and dog. Acinar cells of the cat, hamster, guinea-pig and to a lesser extent the rat, contain discrete, pale granules and also confluent organelles arising from two to three of the pale particles. Composite, electron-pale secretory units are observed in the dog and rabbit. No correlation could be elicited between the histochemical reactivity of the acinar cells and the content of the secretory enzymes. The relationship between the histochemical reactivity and ultrastructural appearance of acinar cell granules and the organelles containing kallikrein, trypsin-like proteases and amylase seems much more important and functionally relevant. Morphological aspects of the intracellular transport and secretion of granules are discussed.
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  • 58
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    Cell & tissue research 126 (1972), S. 421-430 
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    Keywords: Adrenal cortex ; Rat ; Growth ; Sex-dimorphism ; Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Anhand des Verlaufs des 3H-Index und der Mitoserate in Anhängigkeit vom Lebensalter wurde die Proliferationsaktivität in den Zonen der Nebennierenrinde untersucht. 84 SPF-Ratten erhielten 2 μCi/g 3H-Thymidin i.p.; der Untersuchungszeitraum erstreckte sich vom 18. Trächtigkeitstag bis zur 12. Lebenswoche. Alle Zonen zeigten in der Rangfolge Glomerulosa — Fasciculata — Reticularis eine Abnahme DNS-synthetisierender Zellkerne. Geschlechtsspezifische Unterschiede im Ausmaß der Proliferationsaktivität konnten zu keiner Zeit nachgewiesen werden. Aus der Dissoziation der Kurven des 3H-Index und der Mitoserate bei vergleichbaren DNS-Syntheseraten wird auf eine Änderung der G2-Phase des Generationszyklus der NNR-Zellen in der teilexponentiellen Wachstumsphase geschlossen.
    Notes: Summary In 84 SPF-rats the poliferative activity of the adrenal cortical cells was studied from the 18th day of pregnancy up to 12 weeks post partum. Rats were given 2 μC/g tritiated thymidine and killed 1 hour thereafter. It was shown that there was no sex-related difference in the degree of proliferation that could explain the sexual dimorphism in adrenal weights. In all cortical zones a decrease in the number of labeled cells was seen during the obvservation period. The highest percentage of labeled cells was found in the glomerulosa. There exists no parallelism of the mitotic and labeling index, which gives evidence for a change in length of the G2-phase of the cell generation cycle.
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  • 59
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    Cell & tissue research 126 (1972), S. 446-453 
    ISSN: 1432-0878
    Keywords: Eye ; Manduca sexta ; Ommatidia ; Retinula ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The superposition eye of the sphingid moth, Manduca sexta was explored by means of the scanning electron microscope (SEM). Specifically examined were the corneal nipple array, corneal lens, crystalline cones and tracts, photoreceptor cells and their axons. Descriptions of the external ultrastructure of the components were correlated, where possible with previously published accounts of internal ultrastructure as obtained from TEM studies. A key finding was the demonstration of the axial rotation of the eccentrically situated retinular cell, its externally noted prominence and the arrangement of the other photoreceptor cells composing the retinula. Because of the interest in superposition eye theory, the functional significance of various preretinular optic components was reviewed where it specifically related to Manduca.
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  • 60
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    Cell & tissue research 127 (1972), S. 34-49 
    ISSN: 1432-0878
    Keywords: Cephalic kidney insects ; Diplura ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'ultrastructure du rein labial céphalique deCampodea chardardi Condé a été étudiée. Cette néphridie comprend trois parties: le saccule terminal, le labyrinthe et le canal excréteur. Les cellules du saccule sont des podocytes typiques, contenant de nombreuses vacuoles de pinocytose et des inclusions diverses. La lumière est envahie par des micro-organismes bacilliformes. Le labyrinthe possède des cellules à indentations basales profondes avec de nombreuses mitochondries, et des microvilli distaux. Le canal excréteur débouchant sur la face ventrale du labium est caractérisé par la présence d'une intima cuticulaire. Le rein labial des Diploures a été comparé avec des organes segmentaires néphridiens d'autres Arthropodes, et avec le néphron des Vertébrés.
    Notes: Summary The ultrastructure of the cephalic labial kidney ofCampodea chardardi Condé has been studied. Each nephridium is subdivided into three segments: end-sac, coiled tubule and efferent-duct. The cells of the sacculus are typical podocytes, and contain numerous pinocytotic vesicles and various vacuoles. The lumen contains micro-organisms. The cells of the coiled tubule bear basal infoldings with numerous mitochondria and distal microvilli. The efferent duct terminates close to the ventral face of labium, and possesses characteristic cuticular intima. The labial kidney of Diplura is compared with published data on the nephridial organs of other Arthropods and Vertebrate nephron.
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  • 61
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    Cell & tissue research 127 (1972), S. 175-188 
    ISSN: 1432-0878
    Keywords: Vitelline membrane ; Chorion ; Ephestia ; Follicle cell ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural studies on developing egg chambers of the moth, Ephesita kühniella reveal that the precursors of the vitelline membrane are synthesized within follicle cells which are in contact with the oocyte. The vitelline membrane precursors appear to be synthesized by the rough-surfaced endoplasmic reticulum, and this material apparently moves to the Golgi cisternae where the definitive vitelline membrane precursor body is produced. The previtelline bodies are then secreted into the spaces between the oocyte and follicle cells, where they fuse to form a continuous membrane. Chorion formation begins with the deposition of a layer of tubules at the outer edge of the vitelline membrane which coalesce to form the inner edge of a thin, striated layer. In subsequent stages, several compartmented layers are rapidly secreted external to the striated layer, giving rise to the mature chorion.
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  • 62
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    Cell & tissue research 127 (1972), S. 356-373 
    ISSN: 1432-0878
    Keywords: Complex eye ; Formica polyctena ; Receptors ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Analyse der Feinstruktur des Komplexauges der Ameise Formica polyctena ergab, daß der dioptrische Apparat der insgesamt 750 Ommatidien aus einer lamellierten Cornealinse und einem euconen Kristallkegel besteht. Zwei Hauptpigmentzellen umgeben schalenförmig den Kristallkegel, 8 Nebenpigmentzellen schirmen das Ommatidium in seiner ganzen Länge von der Cornea bis zur Basalmembran ab. Jedes Ommatidium besteht in seinem distalen Teil aus 8 Retinulazellen, 2 gegenüberliegenden schmalen und je 3 gegenüberliegenden großen Sehzellen. Weiter proximal tritt eine 9. Retinulazelle hinzu. Die Mikrovillisäume der Sehzellen verschmelzen zu einem zentralen Rhabdom. Im distalen Teil sind die Mikrovilli in 3 Richtungen angeordnet. Es wird im besonderen die Orientierung der Mikrovilli zur Augenlängsachse und zur Ommatidien-Symmetrieachse untersucht. Auch die 9. Sehzelle bildet Mikrovilli. Das Rhabdom endet an 4 basalen Pigmentzellen. Auf den Mikrovillisaum folgt im Querschnitt des dunkel adaptierten Ommatidiums ein Kranz von großen intrazellulären Vakuolen. Die anschließende cytoplasmatische Zone der Retinulazellen enthält viele Pigmentgranula und Mitochondrien; multivesikuläre und multilamelläre Körper sowie Golgiapparate treten nur selten auf. Die funktionelle Bedeutung des Ommatidienaufbaues und die Verteilung der Organellen bei Dunkeladaptation werden diskutiert.
    Notes: Summary The fine structure of the compound eye of the ant Formica polyctena was investigated. The eye consists of a total of 750 ommatidia, each containing a dioptric apparatus of a lamellated cornea lens, a eucone-type crystalline cone, and 8 long pigment cells which surround the ommatidium for its total length, i.e. from the cornea to the basal membrane. Each ommatidium has in its distal portion 8 retinula cells—6 large plus 2 small ones. The retinula cells are arranged in such a way that 3 pairs of large cells, and the one pair of the small cells lie opposite each other. Further proximally, a 9th retinula cell is encountered. The fused, centrally located rhabdom is built up by the microvilli of all nine retinula cells. The rhabdom ends at 4 basal pigment cells. In dark adapted ommatidia, a ring of large intracellular vacuoles is to be seen immediately peripherally to the rhabdom. The outer, cytoplasmic zone of the retinula cells contains many pigment granules and mitochondria; multivesicular bodies, onion bodies and Golgi apparatus are of relatively rare occurrence. The functional significance of the ommatidial structure and the arrangement of the cell organelles in the dark adapted condition are discussed.
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  • 63
    ISSN: 1432-0878
    Keywords: Olfactory tubercle ; Rat ; Degeneration ; Synapse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The olfactory tubercle of the rat was studied by electron microscopy both in the normal and after ipsilateral olfactory bulb ablation at survival times of from 14 hours to seven days. Particular emphasis was placed on synaptic structures and their changes following the lesion. Normal synapses are similar to those described in previous studies and presynaptic profiles are of at least three types. Types-A and -B contain round vesicles and form asymmetrical contacts and type-C profiles contain flattened vesicles and form symmetrical contacts. There appear to be two major types of degenerative changes. The electron-lucent type predominates at early survival times and is seen first at 14 hours. These profiles show an early reduction in numbers of vesicles with mitochondrial swelling followed by shrinkage of the profile. These profiles become increasingly electron-dense at later survival times. The second major type of degenerating profile is initially electron-dense. The earliest changes in these profiles are an increased axoplasmic density and increased microtubular density and clumping without apparent loss of vesicles. These profiles also become progressively more electron-dense at longer survival times. The observations are discussed in relation to previous reports.
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  • 64
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    Cell & tissue research 128 (1972), S. 303-316 
    ISSN: 1432-0878
    Keywords: Spermatozoon ; Nemertine ; Ultrastructure ; Phylogeny
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Mature spermatozoa of the hoplonemertine, Emplectonema neesii were studied by light and electron microscopy. The spermatozoa are flagellate and motile, each gamete consisting of an elongate anterior head and a posterior flagellar tail. Three regions are identifiable in the head, the acrosome, a nuclear zone and a connecting piece containing two centrioles. The nuclear zone contains glycogen granules as well as an elongate, grooved nucleus and a large mitochondrion whose lobes interdigitate with the nuclear grooves. The flagellum has a typical 9 + 2 flagellar tubule organisation. Nemertine spermatozoan ultrastructure, as exemplified by that of E. neesii, is compared with that of platyhelminth male gametes and the supposed phylogenetic affinity of the two taxeis reexamined in the light of the results of this comparison.
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    Cell & tissue research 128 (1972), S. 241-282 
    ISSN: 1432-0878
    Keywords: Ovary ; Bruchidius obtectus ; Oocytes ; Previtellogenesis ; Ultrastructure ; Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Im ersten Teil der Arbeit werden die Ovariolen adulter Imagines von Bruchidius obtectus licht- und elektronenmikroskopisch untersucht. Durch den Nachweis von Nährsträngen, die die Oocyten mit den Nährzellen der Endkammer verbinden, konnte erstmals gezeigt werden, daß Bruchidius telotroph-meroistische Ovariolen besitzt. Die Nährzellen, deren Kerne kettenförmige Nukleolen aufweisen, bilden bei den Imagines ein Syncytium, das von einem räumlichen Maschennetz aus interstitiellen Zellen stabilisiert wird. In den Oocytenkernen entsteht während der Prävitellogenese eine Karyosphäre, von der aus „Nukleolarkörper“, Binnenkörper und „segmentierte Längsstrukturen“ gebildet werden. Die „Nukleolarkörper“ und die kettenförmigen Nährzellnukleolen werden als multiple Nukleolen diskutiert. Der zweite Teil der Arbeit stellt eine ontogenetische Untersuchung des Ovariolengewebes dar. Danach entsteht das Nährzellsyncytium in der Phase der Imaginalhäutung aus einem zellulär-fusomalen Verband. Die morphologische Abgrenzung der Ei- und Nährzellen voneinander sowie die Ausbildung von Nährsträngen finden ebenfalls in dieser Entwicklungsphase statt. Die präsumptiven Ei- und Nährzellen durchlaufen auf dem Puppenstadium das Pachytän der Prophase der Meiose. Damit weisen sich die Nährzellen als Keimbahnabkömmlinge aus. Im dritten Teil der Untersuchungen erfolgt eine Analyse der DNA- und RNA-Synthese sowie des RNA-Transports in dem Ovariolengewebe adulter Imagines. DNA Markierungen mit 3H-Thymidin lassen auf einen, wenn auch geringen, Polyploidiegrad der Nährzellkerne schließen. Markierungen mit 3H-Uridin belegen eine hohe RNA-Syntheserate der Nährzellkerne. Mit nahezu gleicher Intensität wie die Nährzellkerne synthetisieren auch die Oocytenkerne RNA, obwohl sie eine Karyosphäre bilden. Mit Hilfe von Markierungsgradienten im Ooplasma sowie von Nährstrangmarkierungen gelang der Nachweis eines RNA-Transportes von Nährzellsyncytium über die Nährstränge in die Oocyten. Abschließend wird das telotrophe Ovar von Bruchidius (Coleoptera-Polyphaga) dem telotrophen Ovar der Heteropteren gegenübergestellt. Der Vergleich legt eine konvergente Entwicklung dieses Ovartyps bei Insekten nahe.
    Notes: Summary In the first part of the investigation the ovarioles of adult imagines are analyzed by light and electron microscopy. It is shown that nutritive cords connect the oocytes with the apical trophic tissue, demonstrating that Bruchidius has telotroph-meroistic ovarioles. The trophic tissue, in which the nurse cell nuclei contain chain-like nucleoli, is a syncytium stabilized by a three-dimensional network of interstitial cells. During previtellogenesis, a karyosphere is formed in oocyte nuclei in which “nucleolar bodies”, endobodies, and “filament bodies” originate. The “nucleolar bodies” and the chain-like nucleoli of nurse cells are considered to be multiple nucleoli. In the second part, the development of the ovariole tissue during ontogenesis is studied. The syncytial trophic tissue derives from a cellular-fusomal organization during the phase of molting. During the same period, the morphological distinction between nurse cells and oocytes as well as the development of nutritive cords take place. Nurse cells are derived from the germ-line, since, during pupal stages, both the prospective oocytes and the prospective nurse cells undergo the prophase of meiosis up to pachytene. The third part is an investigation of DNA- and RNA-synthesis and RNA-transport in the ovariole tissue of adult imagines. DNA labelling with tritiated thymidine shows a small degree of polyploidisation in nurse cell nuclei. By labelling with tritiated uridine, a high rate of RNA-synthesis could be demonstrated in nurse cell nuclei. A similar amount of RNA-synthesis exists in oocyte nuclei, even if they form a karyosphere. The transport of RNA from the apical trophic tissue via the nutritive cords into the oocytes is demonstrated by silver grain gradients over the ooplasm and by the labelling of nutritive cords. Finally, the telotrophic ovary of Bruchidius (Coleoptera-Polyphaga) is compared with the telotrophic ovary of Heteroptera, suggesting a convergent development of telotroph-meroistic ovaries in insects.
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    Cell & tissue research 128 (1972), S. 426-437 
    ISSN: 1432-0878
    Keywords: Spermathecal gland ; Silphidae ; Cell types ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Chez les Silphes et en particulier chez Phosphuga atrata, la glande de la spermathèque présente une structure particulière liée à la présence d'une intima cuticulaire tapissant la lumière de la glande. Elle comporte trois types cellulaires: les cellules sécrétrices, les cellules de l'épithélium sous-cuticulaire et les cellules-manchons. Les cellules sécrétrices de grande taille contiennent une invagination de la membrane cytoplasmique formant une «vacuole» extracellulaire bordée de microvillosités. Dans cette vacuole plonge l'extrémité, différenciée en ampoule poreuse, d'un canalicule de nature cuticulaire, qui véhicule la sécrétion jusqu'à la lumière de la glande. Le canalicule est élaboré par une cellule-manchon qui l'accompagne sur toute sa longueur sauf à son extrémité intravacuolaire. Ce type de glande, qui se retrouve chez de nombreux Insectes, y assurant des fonctions diverses (sécrétion odorifique, sécrétion de défense, sécrétion spermale, etc.), est susceptible de nombreuses variations.
    Notes: Summary The spermathecal accessory gland in the female of Phosphuga atrata (Silphidae), exhibits a special structure which is due to the presence of a cuticular intima lining the lumen. The wall of the gland shows three cellular types: the secretory cells, the epithelial cells and the ductule carrying cells. Each large secretory cell contains a cavity formed by an invagination of the cytoplasmic membrane and lined by many microvilli. The secretory cell is connected with a cuticular ductule ending in the cavity of the glandular cell, in a porous organelle. This ductule, which carries the secretory material to the lumen, is surrounded by the ductule carrying cell. This type of integumentary gland is very common in insects, where it assumes various functions (attraction, defense, conservation of sperm, etc.) and its morphology varies considerably.
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    Cell & tissue research 128 (1972), S. 538-554 
    ISSN: 1432-0878
    Keywords: Arteries ; DOCA hypertension ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the unconstricted superficial epigastric and femoral arteries is described in normal rats and in animals with hypertension induced by unilateral nephrectomy, by subcutaneous injections of desoxycorticosterone acetate and drinking of 1% NaCl. The femoral artery showed by far the greater response to the DOCA-saline treatment. In both vessels, the smooth-muscle cells changed from the normal spindle shape to a blunt ended outline with numerous pinocytotic vesicles and prolific collagen production. With long term hypertension, particularly in the femoral artery, the smooth-muscle cell profiles became very irregular. Hypertrophy of the organelles of the smooth-muscle cells was associated with an increase in the intercellular material which gradually changed from a mainly collagenous character to mainly vesicular. Lysosomal activity indicated cell disintegration. White blood cells adhere to the endothelium in hypertensive rats and there was an increase in subendothelial material. The number of intimal smooth-muscle cells increased noticeably in the femoral artery. In both arteries, the adventitial fibroblasts hypertrophied in hypertensive rats. In animals with an elevated blood pressure the morphological response was observed as early as 4 to 7 days after initiation of treatment.
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    Cell & tissue research 129 (1972), S. 92-113 
    ISSN: 1432-0878
    Keywords: Neurosecretion ; Neurohypophysis ; Neurosecretory granule ; Rat ; Membranes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neurosecretory granules (NSG) of rat posterior pituitary glands were prepared by differential centrifugation techniques mainly according to the procedure as described by Barer, Heller and Lederis (1963). As revealed by electron microscopy, the recovery of neurophysin and the contents of enzymes, purified NSG were obtained in a pellet at 30 000 g/60 min (0.44 M sucrose). Eighteen h after injection of (35S) cysteine into the supraoptic nucleus 60% of the recovered radioactivity in the neural lobe was found in the NSG, whereas 20% was found in the final supernatant (100 000 g/120 min). Sixteen days after injection the NSG and the final supernatant fraction contained fairly equal amount of (35S) cysteine (approximately 40%). It is suggested that after a period of intragranular maturation neurophysin is extruded into an extragranular pool of neurosecretory material. With the use of conventional polyacrylamide-gel electrophoresis it was shown that the predominating proportion of radioactivity in the NSG after a hypothalamic injection of (35S) cysteine was located within the neurophysin fraction A and in fraction B. Fraction B is suggested to be partly bound to the NSG membranes. When the NSG soluble and NSG insoluble proteins, obtained after lysis of NSG, were separated on polyacrylamide gels in the presence of sodium dodecylsulphate, the highly radioactive soluble protein was shown to consist of two components with average molecular weights of 12 300 and 14 600. Most of the proteins in the lysate were found in the NSG membranes, though less radioactive. A component with a mol.wt. of 37 000 was enriched in the membrane fraction. At longer times after isotope injection the high mol.wt. proteins, particularly those of the NSG membranes, contained increased amounts of radioactivity.
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  • 69
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    Cell & tissue research 130 (1972), S. 18-27 
    ISSN: 1432-0878
    Keywords: Oocytes ; Chilopoda ; Vitellogenesis ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Dans l'ovocyte de Lithobius forficatus L., les trois types classiques de réserves vitellines apparaissent successivement: glycogène, globules lipidiques et vitellus protéique. La synthèse du glycogène semble effectuée au contact des membranes ergastoplasmiques. Les globules lipidiques paraissent élaborés à partir d'un matériel qui transite par le reticulum puis l'appareil de Golgi. Le vitellus protéique est d'origine exogène et pénètre dans l'ovocyte par pinocytose. L'ovocyte mûr est très riche en réserves vitellines et ne renferme qu'une mince couche cytoplasmique périphérique, pauvre en organites.
    Notes: Summary In the oocyte of Lithobius forficatus L., the three classical types of vitelline reserves appear successively: glycogen, lipid droplets, and protein yolk. Glycogen synthesis seems to occur in contact with the rough endoplasmic reticulum. Lipid droplets appear to be elaborated from a material which passes through the endoplasmic reticulum and the Golgi apparatus. Protein yolk originates elsewhere and enters the oocyte by pinocytosis. The mature oocyte is almost completely filled with yolk. There remains only a thin outer coat of cytoplasm with very few organelles.
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  • 70
    ISSN: 1432-0878
    Keywords: Epidermis ; Snails (Lymnaea stagnalis, Biomphalaria pfeifferi) ; Histochemistry ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The epidermis and the associated subepidermal gland cells of the freshwater snails Lymnaea stagnalis and Biomphalaria pfeifferi were studied by means of histochemical and electron microscope techniques. The single cell layered epidermis is composed of general epidermal cells, cilia cells and a few scattered goblet cells. The foot sole and the epidermal regions of the pneumostome and the ventral surface of the lips near the mouth consist nearly entirely of cilia cells; elsewhere the cilia cells are found scattered among the general epidermal cells. The apical layer of the general epidermal cells bear microvilli. Numerous mitochondria, vesicles and lysosomes are located in the apical region of the cells. Several Golgi bodies and a poorly developed granular endoplasmic reticulum occur in the supranuclear region; the nucleus lies in the basal part of the cell. The general epidermal cells in the mouth region contain numerous microfilaments compared to the general epidermal cells in the rest of the epidermis. The cilia of the cilia cells in the densely ciliated regions possess well developed roots and basal bodies interconnected by means of the basal feet. With regard to the other cell organelles, cilia cells are quite similar to the general epidermal cells. For comparison a brief study of the ultrastructure of the epidermis of the terrestrial snail Helix aspersa was carried out. The skin of the snail is covered by a mucous layer produced by various gland cells. In L. stagnalis, in addition to the epidermal goblet cells, thirteen subepidermal gland cell types could be distinguished. The histochemistry of the gland cell types is reflected in the ultrastructure. Three of the gland cell types have an ubiquitous distribution, four types are peculiar to the foot, two types to the lips and five types to the mantle. In B. pfeifferi one epidermal gland cell type and only seven subepidermal gland cell types could be distinguished. Most of these gland cells are limited in their distribution to the foot, lips and mantle edge. The observations may provide a basis for further study in the functions of the snail epidermis.
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  • 71
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    Cell & tissue research 131 (1972), S. 31-45 
    ISSN: 1432-0878
    Keywords: Synapse ; Ultrastructure ; Giant fibre ; Crayfish
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of synapses between the cord giant fibres (lateral and medial) and the motor giant fibres in crayfish, Astacus pallipes, third abdominal ganglia have been examined. These electrotonic synapses are asymmetrical, they have synaptic vesicles only in the presynaptic fibre, and they have synaptic cleft widths normally of about 100 Å but narrowed to about 50 Å in restricted areas. Localized increases in density of the synaptic cleft and adjacent membranes also occur within a synapse, and synaptic vesicles are most tightly grouped at the membrane in such areas. Tight or gap junctions with 30 Å or narrower widths have not been found, but the junctions probably function in a similar way to gap junctions. Three small nerves are closely associated with the synapses between the giant fibres. One of these small nerves has round synaptic vesicles and is thought to be excitatory on morphological grounds; one has flattened vesicles and is thought to be inhibitory; and one is postsynaptic to the lateral giant and the two small presynaptic nerves. It is proposed that these small nerves modulate activity in the much larger giant fibre synapse.
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  • 72
    ISSN: 1432-0878
    Keywords: Muscle tissue ; Pentastomid ; Body wall ; Parasite ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the body wall muscle of the pentastomid Reighardia sternae is described. The muscle fibres are separated from one another and form two layers, circular and longitudinal. They are cross-striated with approximately 11 actin filaments surrounding each myosin filament. The T-system consists of simple in-pushings of the sarcolemma. The SR is also simple and forms both dyadic and triadic contacts with the T-system tubules and dyadic contacts with the sarcolemma. Electron-dense inclusions occur, usually in the vicinity of the Z-lines, and it is suggested that these may be composed of unsaturated lipids.
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  • 73
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    Cell & tissue research 131 (1972), S. 99-107 
    ISSN: 1432-0878
    Keywords: Median eminence ; Rat ; Exocytosis ; Micro-pinocytosis ; Releasing factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Exocytosis has been demonstrated by electron microscopy in the external zone of the median eminence of the rat. Exocytotic profiles have been observed in nerve fibres characterized by the presence of granular vesicles with median diameters of 90–103 nm and agranular vesicles of about 50 nm. In addition to the small agranular vesicles, coated vesicles of the same size have been found in many nerve fibres, suggesting that at least part of the agranular vesicles in the median eminence originate by micro-pinocytosis. The nature of the fibres showing exocytosis is discussed. Attention is drawn to the possibility of identifying types of fibres in the median eminence by the occurrence of exocytosis.
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  • 74
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    Cell & tissue research 133 (1972), S. 59-86 
    ISSN: 1432-0878
    Keywords: Compound eyes ; Coleoptera ; Ultrastructure ; Dark-light-adaptation ; Irregularities
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The structures of the eyes of two Staphylinid beetles, one large (Creophilus erythrocephalus—18 mm in length) and one small (Sartallus signatus—3 mm in length), were compared. 1. The gross structure of the two eyes is the same: a) biconvex corneal lens, b) crystalline cone of “acone type”, c) narrow crystalline thread and thickening of cone cell extensions just above the rhabdom, d) seven retinula cells plus one basal cell, and e) almost the same corneal refractive index and optical properties of the corneal cuticle. Considerable differences exist in size, shape and arrangement of rhabdom, retinula cells and their axons. The smaller size of the eye of Sartallus is caused by reduction of number of facets rather than cell size, and, in fact, retinula cells and rhabdom have been found to be larger in the smaller beetle. 2. Structural changes during dark-light-adaptation affect crystalline cone, position of screening pigment and size of intercellular spaces between the retinula cells. In the dark-adapted state the cone retracts a little and the crystalline tract becomes wider. A thickening of cone cell extensions occurs just above the rhabdom. Screening pigment migrates to a more distal position and intercellular spaces between the retinula cells considerably increase in size as compared with the light-adapted eye. 3. Both eyes are rich in irregularities. An attempt to classify anomalies of compound eyes has been made. The number of cone cells and principal pigment cells varied, in some cases, from 1–5 and 0–3 respectively. Basal retinula cells did not always contribute to the rhabdom. 4. Interferometrical observations reveal the extreme optical homogeneity of the entire corneal cuticle of the eyes of both species. No layers of different refractive index or optical separation of adjacent ommatidia can be found. The refractive index of the cornea of Creophilus is 1.469; that of Sartallus is 1.488. 5. Functional consequences of the changes which occur during dark-light-adaptation are discussed. Exposure to intense light appears to cause a rapid aging of retinula cells, which is indicated by an increase of onion- and multivesicular bodies.
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  • 75
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    Cell & tissue research 131 (1972), S. 497-517 
    ISSN: 1432-0878
    Keywords: Granulosa cells ; Oocyte ; Pig ; Mitochondria ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pig oocytes and their surrounding granulosa cells obtained from mature Graafian follicles at a stipulated time near to ovulation were studied in some details electronmicroscopically. Particular emphasis is given to the corona radiata cell processes and to the heterogeneous population of mitochondria in the oocyte. The corona radiata cell processes contain various components such as filaments, mitochondria, multivesicular bodies and lipid droplets in their matrix. The contact relationship of the corona radiata cell processes to the oocytes is maintained by desmosomes. Usually, the two parallel surface membranes forming the desmosome are separated by a space of about 200 Å. Occasionally, the two membranes approximate each other to form a junction having a “gap” of about 70 Å. Apparently the membranes become fused in some regions. Of particular interest is the distribution and structural characteristics of the single-membrane-bounded structures, and their relationship to the cytomembranes and the mitochondria. On the basis of the present and earlier (Norberg, 1972) observations, the question arises whether the formation and development of mitochondria of pig oocytes depend, at least partly, on a metamorphosis of single-membrane-bounded structures derived from less complex membraneous elements. Final conclusions concerning this problem demand integrated morphological and biochemical investigation regarding the biosynthesis of mitochondria.
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  • 76
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    Cell & tissue research 131 (1972), S. 545-557 
    ISSN: 1432-0878
    Keywords: Pars intermedia ; Hypothalamus ; Anurans ; Hormone release ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The ultrastructure of the pars intermedia of Rana catesbeiana tadpoles was studied following isolation from the hypothalamus, in vivo after sectioning of the pituitary stalk, and in vitro after implantation of the pituitary into a piece of tail fin. Both experimental procedures were followed by rapid and sustained skin darkening. Pituitaries from normal light and dark adapted tadpoles served as controls. In 4-hour disinhibited glands, melanotrophs revealed hyperactive Golgi bodies, colloid vesicles (1–2 microns) in close proximity to axon terminals, and no apparent loss of secretory granules. At 24 hours extracellular colloid adjacent to axon terminals was found, and extensive arrays of RER appeared in the melanotrophs. Obvious granule loss from secretory cells occurred within a week, by which time the cytoplasm was occupied by large cisterns of SER and RER and abundant free ribosomes. Dense core vesicles (600–900 Å) in aminergic nerve terminals disappeared shortly after isolation of the pituitary from the hypothalamus, and only decreasing numbers of translucent vesicles (200–300 Å) were found. The functional significance of these changes is discussed, with particular emphasis on the mode of acute hormone release.
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  • 77
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    Cell & tissue research 132 (1972), S. 25-34 
    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Rat ; Perivascular cells ; Neurosecretion ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The purpose of this study is to investigate the ultrastructural features of perivascular cells as found in the neural lobe of the hypophysis. In particular, an inquiry was made into the nature of the relationship of such cells to neurosecretory fibers and endings. The latter, in fact, are often invaginated within the perivascular cells and enveloped by their processes; furthermore, they often reveal a certain number of empty granules as well as characteristics of degenerative nature. In the course of this study the localization of the perivascular cells has been investigated as well as that of their processes within the extensive interlobular network typical of the hypophysial neural lobe of rodents. Based on the data gathered, the hypothesis is put forward that the perivascular cells play an important role in the turnover of neurosecretory endings, both under physiological and experimental conditions, contributing thereby to the release of post-hypophysial hormones.
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  • 78
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    Cell & tissue research 132 (1972), S. 51-65 
    ISSN: 1432-0878
    Keywords: Salivary glands ; Octopus ; Innervation of musculature ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé Les fibres nerveuses, souvent composées, qu'on peut trouver dans le tissu conjonctif séparant les fibres musculaires du canal, ou les tubules de la glande, sont très comparables morphologiquement aux fibres des troncs moteurs. Leurs cellules satellites, qui contiennent de grosses inclusions, nombreuses et très denses aux électrons, engainent les axones pratiquement jusqu'au niveau des terminaisons. Les jonctions neuromusculaires sont caractérisées par l'accumulation de petites vésicules claires, accompagnées de quelques vésicules plus grandes et à »coeur« dense. Les axones présentent aussi le long de leur trajet des segments plus ou moins dilatés où existent des vésicules de types très variés, et dont la signification est discutée.
    Notes: Summary Nervous fibers, often composite, can be found in the connective tissue between the duct muscular fibers, or the gland tubules. They are morphologically similar to the motor trunks fibers. Their satellite cells, containing numerous electron-opaque large inclusions, can be seen round the axons nearly to the nerve endings. Neuromuscular junctions are characterized by the accumulation of small clear vesicles, intermingled with some larger dense-cored vesicles. Axonal swellings, with numerous vesicles of various types, can also be seen along the course of the nerve fibers; their significance is discussed.
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    Cell & tissue research 133 (1972), S. 463-474 
    ISSN: 1432-0878
    Keywords: Teleost ; Ultrastructure ; Red muscle ; White muscle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Es wurden die Feinstruktur roter und weißer Muskelfasern des Seewasserteleostiers Seelachs (Gadus virens) untersucht und ultrastrukturelle Messungen und Analysen durchgeführt. Die Sarcomerlängen der roten Fasern liegen zwischen 1,60 und 1,82 μ, die der weißen zwischen 1,70 und 1,85 μ. Hinsichtlich des prozentualen Vorkommens von sarcoplasmatischem Reticulum und T-System bestehen zwischen roten und weißen Fasern keine wesentlichen Unterschiede. Beide Fasertypen zeichnen sich durch regelmäßiges Vorkommen von Triaden am Z-Streifen, deutliche M-Streifen und multiple Innervation aus. Ultrastrukturell unterscheiden sich die beiden Fasertypen dadurch, daß die roten Fasern dickere Z-Streifen und mehr Mitochondrien, die weißen peripher bandförmige Myofibrillen besitzen. Die Struktur der Fasern dieser beiden Muskeltypen wird im Hinblick auf deren mögliche Rolle beim Schwimmen diskutiert.
    Notes: Summary The fine structure of the red and white myotomal muscles of a marine teleost, the coalfish Gadus virens, has been examined and ultrastructural measurements and analyses carried out. The sarcomere lengths of the red and white fibres were found to be 1.60 μ minimum, 1.82 μ maximum and 1.70 μ minimum, 1.85 μ maximum, respectively. No significant difference was found between the red and white fibres in their percentage of sarcoplasmic reticulum and T system. Both were found to have regularly occurring triads at the Z disk level, to have distinctive M lines and to be multiply innervated. Ultrastructurally the two fibres can be distinguished by the thicker Z line and more abundant mitochondria of the red fibre, and by the ribbon-shaped peripheral myofibrils of the white fibres. The structure of the fibres in these two types of muscle is discussed in relation to their possible role in swimming.
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    Cell & tissue research 133 (1972), S. 529-537 
    ISSN: 1432-0878
    Keywords: Statocyst ; Pomacea paludosa ; Ultrastructure ; Cell types ; Ciliary orientation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Ultrastructural observations on the statocysts of the prosobranch gastropod Pomacea paludosa are reported in this paper. 1. The static nerve consists of a great number of naked axons with a diameter of 0.2–0.5 μm. Several axons are joined together to bundles by glia cells (Fig. 1). 2. The epithelium of the statocyst contains 2500–3000 hair (= sense) cells, each with an area of at most 75 μm2 (Fig. 2). This great number of hair cells is compared with the number of receptor cells in other gastropod statocysts. 3. The hair cells are surrounded by smaller supporting cells. The significance of the interlacing of hair and supporting cells and of the possible contact between hair cells is discussed. 4. Supporting cells possess microvilli and sometimes one modified cilium (Fig. 5). The hair cells bear microvilli and 30–40 cilia. These cilia have the typical 9+2 arrangement of the filaments, striated roots to one side of the basal body and a basal foot to the other (Fig. 3). 5. For each sense cell and even for larger areas of the statocyst wall the basal feet point nearly in the same direction (Fig. 4). Hence it is suggested (a) a directional sensitivity for each hair cell and (b) a correlation between the areas of same polarisation and the “groups” of nerve fibers. 6. Different types of vesicles in the nerve layer of the cyst wall (Fig. 6) and stimulation experiments give some evidence for an efferent innervation of the statocysts.
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  • 81
    ISSN: 1432-0878
    Keywords: Ultimobranchial glands ; Urodeles ; Cell types ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of the ultimobranchial (UB) glands of two common laboratory urodeles, viz., larval axolotls, Ambystoma mexicanum Shaw and adult Pleurodeles waltlii Micahelles, is described and compared in what is believed to be the first ultrastructural report on urodele UB glands. The axolotl UB gland shows a wide variety of form, being represented by an elongated diffuse series of follicles and sometimes by one or two large discrete terminal follicular bodies. In these axolotl UB glands up to four cell categories are distinguishable including a tonofilamentous cell and a secretory cell that is possibly homologous with calcitonin-producing C cells of anurans or other vertebrates. These two cell categories are also found in the Pleurodeles gland. The possible significance of the various cells is considered.
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  • 82
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    Cell & tissue research 134 (1972), S. 205-225 
    ISSN: 1432-0878
    Keywords: Diabetes insipidus ; Rat ; Hypothalamo-neurohypophysial system ; Synthesis of hormones ; Light- and Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The general ultrastructural features of the hypothalamo-neurohypophysial system in rats with hereditary hypothalamic diabetes insipidus (DI-rats, Brattleboro strain) are described. There is no decisively distinguishing difference between the neurons of the supraoptic and paraventricular nuclei. The neurons of both nuclei show signs of active protein synthesis. The perikarya of the neurons are markedly hypertrophic, the nuclei are large and the nucleoli prominent. In the cytoplasm there are numerous ribosomes, abundant rough-surfaced endoplasmic reticulum and extensive Golgi complexes. However, very few neurosecretory granules are to be seen. The axons of the hypothalamo-neurohypophysial tract are likewise enlarged and the paucity of neurosecretory granules is a striking feature also in the area of the tract. The majority of nerve endings in the posterior pituitary of DI-rats are devoid of neurosecretory granules. Microvesicles are abundant in the nerve endings and there are findings which suggest that microvesicles are involved either in endoor exocytosis. The signs of active protein synthesis and the concomitant paucity of neurosecretory granules are interpreted to imply transportation of the secretory proteins in an extragranular phase. The possible mode of release of the secretory proteins from the nerve endings and the role of microvesicles therein are discussed.
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    Cell & tissue research 133 (1972), S. 163-179 
    ISSN: 1432-0878
    Keywords: Excretory organ ; Ileum ; Blatella germanica ; Ultrastructure ; Microprobe analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Résumé L'iléon de Blatella germanica est un important segment d'accumulation minérale. Les nombreuses concrétions d'origine ergastoplasmique, contiennent du phosphore, du chlore, du calcium, du magnesium, du potassium et du fer dans un stroma glycoprotéique. La paroi de ce segment protodéal est constituée d'un type cellulaire unique caractérisé par la présence de feuillets apicaux et d'invaginations basales, différenciations membranaires décrites dans d'autres organes de transit, mais dont la coexistence constitue l'originalité de l'iléon. La signification physiologique de ce segment digestif est discutée.
    Notes: Summary The ileum of Blatella germanica is an important proctodeal segment of mineral accumulation. The numerous concretions, elaborated by the ergastoplasm, contain P, Cl, Ca, Mg, K and Fe in a glycoproteic matrix. The epithelium of this segment is composed by only one type of cells which are characterized by apical leaflets and basal infoldings. These membraneous differenciations have been already described in other transit organs, but their coexistence is typical of the ileum. The physiological significance of this digestive segment is discussed.
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    Cell & tissue research 133 (1972), S. 289-325 
    ISSN: 1432-0878
    Keywords: Nematosomes ; Neurons ; Substantia nigra ; Rat and Cat ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Distinctive cytoplasmic inclusions, termed nematosomes, have been identified in the neurons, but not in the glial cells of the substantia nigra in the rat and the cat. These organelles which lack a limiting membrane consist of an entanglement of more or less tightly packed microfilaments or filamentous strands. According to the tridimensional arrangement of their filamentous components, as well as to their size and boundary, the nematosomes usually display several structural types: (a) round or oval, dense, filamentous bodies; (b) reticular inclusions with or without excavated centers; (c) ill-defined small aggregates of fine filaments. At higher magnification, each microfilament or filamentous strand, whatever the type of nematosome, is itself composed of similar subunits, about 20 Å in diameter. It should be pointed out that the latter subunits may be fine deposits of heavy metal on structural components of nematosomes, which appear to be similar in every structure. The ultrastructural organization of a given nematosome may vary from one portion to another. The functional significance of such structural variations from one nematosome to another, and even within a given nematosome, could not be elucidated by means of our ultrastructural study, although additional cytochemical and radioautographic work may throw light on this problem. These cytoplasmic bodies are present in the perikaryon of most neurons and one or more inclusions are usually observed in the same nerve cell. They are infrequently seen in the dendritic or axonal processes. The nematosomes are closely associated with the other cytoplasmic organelles filling the ground substance of neurons by means of microfilaments projecting from their surface. These cytoplasmic inclusions are, however, most frequently linked to surrounding free ribosomes and rough ER profiles. The association of free ribosomes with excavated nematosomes, which in turn contain neurofilaments in their core, suggests that these structures consist, partly at least, of precursor material which is assembled into the structural proteins of the neurofilaments after being synthesized by the neighbouring ribosomes. No special relationship with the neurotubules has been noticed. Nematosomes have also been found in structural relationship with other organelles, i.e. the smooth tubules and vesicles, the Golgi apparatus, the coated vesicles, the lysosomes and the mitochondria. The nematosome may be also closely associated with the subsynaptic web of axosomatic synapses and these two cytoplasmic components display many structural similarities. In the light of these and previously reported observations, it would appear that nematosomes are not incidental cytoplasmic inclusions, but common organelles of certain types of neurons.
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    Cell & tissue research 135 (1972), S. 539-551 
    ISSN: 1432-0878
    Keywords: Pseudoculus ; Eosentomon (Protura, Insecta) ; Sense organ ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung In der Feinstruktur unterscheidet sich der Pseudoculus vonEosentomon nicht wesentlich von dem der Acerentomiden. Durch einen Endokutikulaporus treten die dendritischen Fortsätze zweier Sinneszellen, jeweils umgeben von einer Hüllzelle, in den Außenraum des Pseudoculus ein. Der Außenraum wird nach distal von einer äußeren Kutikulaschicht — vermutlich Epikutikula — abgeschlossen. Sie vermittelt durch regelmäßig angeordnete lange Spalten die Verbindung zur Außenwelt. Am Grunde der Spalten finden sich Porentubuli, die mit den Hüllzellen oder den distalen Fortsätzen der Dendriten Kontakt haben können. Aus der Feinstruktur kann geschlossen werden, daß der Pseudoculus als Chemo-, Hygro- und/oder Thermorezeptor fungiert.
    Notes: Summary Concerning its fine structure the pseudoculus of Eosentomon is quite similar to that of Acerentomide Protura. There are two sensory cells innervating the organ. From each of them one dendritic process derives, surrounded by one enveloping cell. The processes of these four cells enter the distal cavity of the pseudoculus through a pore in the endocuticular layer. The cuticular layer of the cap seems to consist of epicuticle only. It is furrowed by long clefts connecting the distal cavity of the organ with the outside. Poretubules insert at the base of the clefts and may have contact with the cell membranes of both enveloping cells and dendritic processes. According to its structure the pseudoculus may function as chemo-, hygro- and/or thermoreceptor.
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    Cell & tissue research 135 (1972), S. 473-482 
    ISSN: 1432-0878
    Keywords: Neurosecretory nerves ; Glial and pigment cells ; Neural sheath ; Gastropods ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The fine structure of neurosecretory nerves and endings associated with the sheath of the infraesophageal ganglion ofHelix aspersa is described. The sheath is a neurohemal organ whose vascularized stroma receives both monoaminergic and peptidergic endings. The latter occur along the surface of the nerves or scattered within the stroma. They include a complex population of vesicular profiles. The granular vesicles (1300–3000 Å in diameter) exhibit structural modifications that may be related to the intra-axonal release of their neurohormones. The agranular vesicles (500–2000 Å in diameter) occur in large numbers and lie mostly adjacent to the axon surface. Synaptoid specializations seem to represent active sites for the extracellular discharge of neurosecretory material. The monoaminergic endings so far studied lack synaptoid specializations and contain small granular (800–1300 Å in diameter) and agranular (700 Å in diameter) vesicles. Two kinds of non-neural cells are associated with the nerves: glial cells and melanocytes.
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  • 87
    ISSN: 1432-0878
    Keywords: Gonocytes ; Rat ; Mitotic activity ; Autoradiography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Gonocyten der Ratte können in 2 hintereinander geschaltete Keimzellarten gegliedert werden, die I-Gonocyten und II-Gonocyten. Die I-Gonocyten proliferieren bei der Wistarratte zwischen 15. und 18. Fetaltag, die Tochterzellen der I-Gonocyten, die II-Gonocyten treten nach einer Zeitdauer von 7–8 Tagen zwischen 4. und 6. Lebenstag in die Mitose. Auf Grund der gewonnenen Daten erschien es sinnvoll, die mitotische Aktivität der II-Gonocyten und die Bestimmung der Dauer ihrer S-Phase an 5 Tage alten Ratten durchzuführen. Untersuchungen von 50 Zentren mitotischer Aktivität in einem in Serie geschnittenen Hoden einer 5 Tage alten Ratte ergaben, daß 148 von 190 Mitosen, d.s. 78%, in Gruppen und 122, d.s. 64% der Mitosen in „Paaren“ vorkommen. Mit der Methode der markierten Mitosen (Quastler u. Sherman, 1959) und der Methode der Doppelmarkierung (Hilscher u. Maurer, 1962) wurde die Dauer der S-Phase der II-Gonocyten bei 5 Tage alten Ratten bestimmt. Es ergab sich eine gute Übereinstimmung der nach beiden Methoden bestimmten Werte. Die S-Phasen-Dauer der II-Gonocyten dürfte danach am 5. Lebenstag bei 11,0–11,5 Std liegen.
    Notes: Summary The gonocytes of the rat are of two types: I-gonocytes and II-gonocytes. In Wistar rat I-gonocytes proliferate at the beginning of prespermatogenesis between the 15th and 18th day of gestation. Their multiplication stops between the 18th and 19th day. Starting on the 4th postnatal day, II-gonocytes, the daughter cells of I-gonocytes, begin to proliferate. The 5th postnatal day proved to be favourable for studying the mitotic activity and for determing the S-phase of II-gonocytes. In one serially sectioned testis of a 5 days old rat 25 sex cords were reconstructed. Till now 50 centres of mitotic activity of II-gonocytes with 190 mitoses were localized. Only 42 out of the 190 mitoses were isolated, 148 occur in groups. 122 out of the grouped mitoses are in “pairs”. That means that 78% of the grouped and 64% of all mitoses were to be found in pairs. By the method of labeled mitoses (Quastler and Sherman, 1959) and by the method of double labeling with C-14- and H-3-thymidine (Hilscher and Maurer, 1962) the duration of the S-phase of II-gonocytes were determined in 5 days old rats. The results of both methods show that the S-phase is 11.0 to 11.5 hours.
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  • 88
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    Cell & tissue research 125 (1972), S. 210-228 
    ISSN: 1432-0878
    Keywords: Regio olfactoria ; Teleosts ; Anguilla anguilla ; Ultrastructure ; 3 Different receptor types
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Flimmerepithel von Anguilla anguilla besteht aus 4 Zellarten: Flimmerzellen, Stützzellen, Basalzellen und Schleimbecherzellen. Flimmerzellen enthalten im oberen Zelldrittel zahlreiche Mitochondrien und tragen an ihrer Oberfläche bis zu 140 Kinocilien. Die Basalkörper dieser Kinocilien haben lange Wurzelfilamente, von denen ein Teil ins Zellinnere zieht; der andere Teil verläuft parallel zur Oberfläche und verbindet benachbarte Basalapparate. — Ein Übergangsepithel verknüpft das Flimmerepithel mit dem Riechepithel. Im Riechepithel finden sich außer den Zellarten des Flimmerepithels die Rezeptoren. Bei einheitlichem Aufbau des Zellkörpers lassen sich aufgrund rein morphologischer Unterschiede der Vesiculae olfactoriae 3 Rezeptortypen unterscheiden: 1. Cilien-Rezeptor, 2. Mikrovilli-Rezeptor und 3. „Pfriem“-Rezeptor. — Der Cilien-Rezeptor trägt unterhalb der Vesicula olfactoria in einer Einschnürung 4–8 sensorische Cilien, die alle auf gleicher Höhe entspringen. Zwei gegenüberliegende sensorische Cilien schließen einen konstanten Winkel von 60° ein. — Der Mikrovilli-Rezeptor trägt auf seiner abgerundeten Vesicula olfactoria 30 bis 60 Mikrovilli von 0,1 μm Dicke und bis zu 5 μm Länge. Der Mikrovillus wird von einem zentralen, 160 Å weiten, Tubulus durchzogen. Unterhalb der Vesicula olfactoria liegen mehrere Centriolen. Die Rezeptornatur dieser Zellen wird durch ein Axon unterstrichen. — Der „Pfriem“-Rezeptor besitzt eine 0,8 μm breite und bis zu 4 μm lange Vesicula olfactoria ohne sensorische Cilien und ohne Mikrovilli. Im Lumen der Vesicula olfactoria befinden sich neben Neurotubuli auch Fibrillen von 40–50 Å Durchmesser, die gebündelt auftreten. An der Basis des Köpfchens liegen mehrere Centriolen.
    Notes: Summary The ciliary and olfactory epithelia of the olfactory folds in Anguilla anguilla were studied with the electron microscope. The ciliary epithelium is composed of ciliary cells, supporting cells, basal cells, and mucous cells. The ciliary cells contain numerous mitochondria in their apical portion and bear up to 140 cilia. The ciliary basal bodies have rootlets, some of which project towards the central part of the cell, and others parallel to the cell surface thereby connecting neighbouring basal bodies. A transitional epithelium is located between the ciliary and olfactory epithelia. The olfactory epithelium is composed of the same 4 cell types of the ciliary epithelium and besides contains three morphologically different receptor cell types: ciliary receptor cells, microvillous receptor cells, and receptors with a single rodshaped free appendage. The ciliary receptors have 4 to 8 “sensory” cilia which project from below the vesicula olfactoria, each forming a constant angle of about 30° with the vertical cell axis. The vesicula olfactoria of the microvillous receptors bears from 30 to 60 microvilli, each of 0.1 μm diameter and up to 5 μm length. Each microvillus of this receptor type contains a central tubulus of 160 Å diameter. Few centrioles are located closely to the vesicula olfactoria. The third receptor type, which has neither cilia nor microvilli, is characterised by a single rod-shaped appendage of 0.8 μm diameter which projects up to 4 μm above the epithelial surface. This appendage contains neurotubules and fibril bundles; some centrioles lie close to the base of the appendage.
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  • 89
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    Cell & tissue research 125 (1972), S. 277-288 
    ISSN: 1432-0878
    Keywords: Neurohypophysis ; Rat ; Exocytosis ; Freeze-etching ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Neural lobes of rats subjected to severe acute haemorrhage under sodium pentobarbitone anaesthesia were examined electron microscopically and the ultrastructure compared with that in anaesthetised and unanaesthetised controls. Changes in the localisation and numerical distribution of elementary granules and small vesicles in the neurohypophysial nerve endings of bled rats were consistent with the occurrence of exocytosis. The occurrence of “exocytotic profiles” was observed more frequently in freeze-etched tissue samples as compared with the material fixed for conventional electron microscopy. The ratio of small vesicles: elementary granules was shown to be significantly increased (P〈0.005) in the nerve endings of neural lobes from bled rats. Equally, the numbers of exocytotic profiles related to 1000 μm2 of neurohypophysial tissue area were significantly greater (P〈0.005) in bled rats.
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  • 90
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    Cell & tissue research 125 (1972), S. 252-276 
    ISSN: 1432-0878
    Keywords: Amnion-Umbilical-cord-Skin ; Sheep ; Differentiation of the epithelia ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Die Ektoblastderivate Amnion-, Nabelstrang- und Hautepithel von 14 Schaffeten zwischen 1,1 und 44 cm SSL wurden elektronenmikroskopisch untersucht. Das Amnionepithel ähnelt dem anderer Säuger; die tonofibrillenreichen Zellen sind mit Mikrovilli besetzt, seitlich sind sie stark miteinander verzapft. Das Schlußleistennetz bleibt bis zur Geburt erhalten. Der Golgiapparat ist kräftig entwickelt. Glatte Mikropinozytosevesikel von 600–800 Å Ø am basalen und seitlichen Plasmalemm werden mit fortschreitender Entwicklung zahlreicher. Größere Vakuolen fehlen. Das Nabelstrangepithel bleibt im Gegensatz zu anderen Spezies ein geringfügig modifiziertes Amnionepithel ohne eigene Differenzierung. In der zweiten Trächtigkeitshälfte sind die Interzellularräume durchschnittlich weiter als im peripheren Amnionepithel. Mikropinozytosebläschen kommen auch an apikalen Mikrovilli vor. Die Epidermis ist schon im einschichtigen Stadium nicht amnionähnlich, die apikalen Mikrovilli sind wesentlich spärlicher und kürzer, die Interzellularräume sind oft einfacher geformt, basal finden sich bereits Hemidesmosomen. Bei größeren Feten werden die Interzellularräume sehr eng, die Mikrovilli stehen in Gruppen. Weder in den glykogenbeladenen Peridermzellen noch in den Basalzellen sind Pinozytosevesikel, Fruchtwasservakuolen oder andere Indizien für einen Fruchtwassertransport zu finden.
    Notes: Summary The ultrastructure of the derivates of the ectoblast, the epithelia of the amnion, umbilical cord and skin has been studied in fetal sheep ranging from 1.1 to 44 cm CRL. The amniotic epithelium is similar to that of other mammals. The cells are rich in tonofilaments, they carry microvilli and are interdigitated with one another. Terminal bars are retained until birth. The Golgi apparatus is well developed. Smooth micropinocytotic vesicles with a diameter of 600–800 Å on the basal and intercellular cell membranes become more numerous with progressing development. Larger vacuoles are missing. The epithelium of the umbilical cord, contrary to that of other species, remains a slightly modified amniotic epithelium without special differentiation. The intercellular spaces are on the average wider in the second half of pregnancy than those in the peripheral amniotic epithelium. Micropinocytotic vesicles occur also on the apical microvilli. In the single layer stage the epidermis is dissimilar to that of the amniotic epithelium. The apical microvilli are far less numerous and shorter, the intercellular spaces are often of a more simple structure. Hemidesmosomes occur in the basal cell membrane. Later the intercellular spaces become very narrow, the microvilli are present in clusters. Pinocytotic vesicles, amniotic fluid vacuoles or other indications of amniotic fluid transport are to be found neither in the glycogen-rich peridermal cells, nor in the basal cells.
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  • 91
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    Cell & tissue research 125 (1972), S. 289-294 
    ISSN: 1432-0878
    Keywords: Accessory optic system ; Rat ; Blood vessels ; Extracellular space ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Two types of capillaries were found in the medial terminal nucleus of the rat accessory optic system. Type one capillaries are surrounded by glial processes and lack a perivascular space, whereas the type two capillaries and arterioles show a distinct extracellular perivascular space often filled with collagen fibrils. An internal as well as an external basal lamina lines these spaces. No fenestration of the endothelium was observed.
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  • 92
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    Cell & tissue research 124 (1972), S. 1-11 
    ISSN: 1432-0878
    Keywords: Spermiogenesis ; Rat ; Spermatids ; Manchette ; Microtubules
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The manchette or caudal tube has been examined in Stage 14 rat spermatids. The microtubules of the caudal tube have been found to be partially sheathed by smooth endoplasmic reticulum which appears to be continuous with the outer nuclear membrane of the redundant nuclear envelope. The microtubules in caudal regions of the manchette have been noted to be interconnected by links of unusual size and morphology. It is suggested that the caudal tube consists at this stage of development of two structures, membrane and microtubules and that the links between the microtubules appear to play a role in the structural order noted in the position of the tubules of the manchette. The possible significance of these links in relation to motility is discussed.
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  • 93
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    Cell & tissue research 124 (1972), S. 217-229 
    ISSN: 1432-0878
    Keywords: Sensory axons ; Dorsal root ganglia ; Rat ; Ribosomes ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the dorsal root ganglia of the rat, ribosomes were found not only in the initial segment, but they were also observed in the axoplasm of intraganglionar myelinated fibres and in the sensory portion of spinal nerves. Axons of seven-days-old rats contained more ribosomes than those of adult animals. The amount of particles decreased gradually from the initial segment trough intraganglionar internodes to the axons of spinal nerves. No ribosomes were found in axons of dorsal roots. In intraganglionar fibres, ribosomal particles were usually observed near the nodes of Ranvier, in the vicinity of Schmidt-Lantermann clefts and in axons near the Schwann cell nuclei. They were arranged in tetrads, pentads or in larger polysomes, and they were often observed adjacent to a group of mitochondria. The particles had invariably a stable size, their average diameters measuring 234 ± 2 × 197 ± 3 Å, which is practically equal to the diameters of 232 ± 2 × 203 ± 3 Å of ribosomes in the Schwann cell cytoplasm. These values fall within the range of diameters of ribosomes isolated from various cells of eukaryotic organisms as given in the literature. Since no other granular component of the cytoplasm has similarly stable dimensions, the measurements are considered to prove that the axonal particles described here are ribosomes.
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  • 94
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    Cell & tissue research 124 (1972), S. 275-292 
    ISSN: 1432-0878
    Keywords: Sensory receptors ; Acarina ; Amblyomma americanum ; Haller's organ ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Hallersche Organ auf dem Tarsus der Zecke Amblyomma americanum (L.) (Acarina: Ixodidae; Nymphenstadium) wurde mit dem Durchstrahlungs- und Rasterelektronenmikroskop untersucht. Es besteht aus einer distalen Sensillengruppe, die in einer flachen „Wanne“ gelegen ist, und einer proximalen „Kapsel“, welche mehrere Sensillen einschließt. Alle sieben Sensillen der „Wanne“ (A1–A7) sind dickwandig und mehrfach innerviert (2–9 Neurone), jedoch können mindestens 3 verschiedene Typen unterschieden werden: A1 und A2 besitzen große Poren (〉1000 Å), die mit Pfropfen versehen sind, und sie sind zudem die einzigen Sensillen mit sich verzweigenden Dendriten; A3 und A5 sind durch eine radspeichenartige Anordnung der Cuticulawandung charakterisiert, ferner durch feine Poren (100–200 Å), welche die Speichen zentral durchziehen; A4, A6, und A7 zeigen kein Porensystem, doch wird eine einzelne Öffnung an der Spitze vermutet. Die „Kapsel“ enthält 7 dünnwandige, stumpf endigende Sensillen und mehrere nichtsensorische Cuticulavorsprünge. Alle Sensillen besitzen große „Pfropfporen“ in der Cuticulawandung und zahlreiche dendritische Verzweigungen mehrerer Neuronen (3–5) im Lumen. Drüsenmündungen wurden in der „Kapsel“ festgestellt, ihre Bedeutung wird diskutiert. Die Feinstruktur des Hallerschen Organs entspricht dem Postulat von Lees (1948), wonach die „Kapsel“ der Geruchsrezeption, die „Wanne“ der Feuchtigkeitsrezeption dienen soll.
    Notes: Summary Haller's organ on the tarsus of the tick Amblyomma americanum (L.) (Acarina: Ixodidae; nymphal stage) was studied by scanning and transmission electron microscopy. It consists of a distal bristle group, (the “anterior pit”), and a proximal “capsule” which encloses several sensilla. The seven sensilla of the anterior pit (A1–A7) are all thick-walled and multi-innervated (2–9 neurons), but at least three different types can be differentiated. Sensilla A1 and A2 possess large, plugged pores (〉1000 Å) and are the only sensilla with branching dendrites. A3 and A5 are characterized by a spoke-wheel arrangement of the cuticle wall and very fine pores (100–200 Å) penetrating the “spokes” centrally; A4, A6, and A7 do not exhibit any pore system but a single opening at the bristle tip is assumed. The capsule contains seven thin-walled, blunt-tipped sensilla, and several non-sensory cuticular projections (pleomorphs). All of these sensilla possess large “plugged” pores in the cuticle wall and numerous dendritic branches of several neurons (3–5) in the lumen. Glandular openings were found inside the capsule; their significance is discussed. The fine structure of Haller's organ supports the functions postulated by Lees (1948), namely olfaction for the capsule and humidity reception (among others) for the anterior pit.
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    Cell & tissue research 124 (1972), S. 465-478 
    ISSN: 1432-0878
    Keywords: Anterior pituitary ; Mouse ; in vitro ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Anterior pituitaries of mice were incubated for periods up to four hours in Krebs-Ringer bicarbonate glucose gassed with 95% O2∶5% CO2. The incubated explants survived and retained a fine structure that approximated the condition in situ. The few necrotic cells were sharply localized, and were found to be due to initial mechanical damage to the tissue. Some cells of the six granulated types exhibited slight but significant changes attributable to the liberation from the hypothalamic control: in LTH cells there was a release of preexisting granules and a development of cell organelles, whereas in other cell types there was an inhibition of release of granules and an enhanced digestion of the accumulated granules by the lysosomal system. Follicular cells responded uniquely to the changed environment by hypertrophy of the cytoplasm and were found to phagocytize cell debris. A part of non-epithelial elements of the gland showed a tendency to modulate cytologically.
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  • 96
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    Cell & tissue research 124 (1972), S. 454-464 
    ISSN: 1432-0878
    Keywords: Lateral-line organ ; Eel (Anguilla japonica) ; Mechanoreceptor ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The sensory epithelium of the lateral line organ of the common eel consists of two types of cells, (sensory and supporting). The sensory cell bears a kinocilium together with about 40 to 60 stereocilia on its surface. The kinocilium is situated either at rostral or at caudal margin of this cilial group. Such polarity of the cilial group of one cell is inverse to that of an adjacent cell. Two types of crystal-like inclusions exist in the sensory cells, consisting of granules 100 Å in diameter. Granules in one type are arranged regularly whereas those in the other rather irregularly. Two types of nerve endings exist at the base of sensory cells: one is predominant in number and contains few vesicles, accompanied by a dense spherical body surrounded by small vesicles in the sensory cell and the other is rare in number and contains many vesicles, accompanied by a small flat sac just beneath the plasma membrane of the sensory cell. The supporting cells contain numerous mitochondria, a well developed Golgi apparatus and rough-surfaced endoplasmic reticulum, and surround a sensory cell completely. Physiologic significance of some of these components is discussed.
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  • 97
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    Cell & tissue research 126 (1972), S. 261-277 
    ISSN: 1432-0878
    Keywords: Adrenal medulla ; Rat ; Cell types ; Secretion ; Influence of fixation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Das Nebennierenmark der Ratte wurde nach Anwendung verschiedener Fixationsmethoden untersucht. Nach Immersionsfixation mit Glutaraldehyd oder Osmiumtetroxyd finden sich in der Nebenniere sog. Mischzellen, helle Zellen, syncytiale oder plasmodiale Zellen, die von den Untersuchern als Artefaktbildungen angesehen werden. In allen Proben nach Perfusionsfixation wurden solche Artefaktbildungen niemals beobachtet. Bei Immersionsfixation wurde eine enge Beziehung zwischen Sekretgranula und Cytoplasmamembran beobachtet, was bei Perfusionsfixation selten der Fall war. Die heutigen Theorien über den Sekretionsmechanismus bei Nebennierenmarkzellen werden aufgrund der vorgelegten Ergebnisse diskutiert. Die Arbeit zeigt die wesentlichen Vorteile der Anwendung der Perfusionsfixation für die Untersuchung der Nebenniere.
    Notes: Summary The adrenal medulla of the rat was studied utilizing various methods of fixation. In adrenal medulla specimens after immersion fixation either with glutaraldehyde or osmium tetroxide, elements such as mixed, clear, syncytial, or plasmodial cells, believed to be of artifactual origin, are observed in all of this material examined. These elements are absent in the specimens prepared by perfusion fixation. In specimens prepared by immersion fixation, secretory granules are found in close proximity to the plasma membrane; this localization is infrequent after perfusion fixation. Current theories of the mechanism of secretion of adrenal medullary hormones are discussed on the basis of our results. This investigation demonstrates the advantage and necessity of perfusion fixation in the study of the adrenal medulla.
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  • 98
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    Cell & tissue research 126 (1972), S. 466-482 
    ISSN: 1432-0878
    Keywords: Macrophages ; Microtubules ; Enamel organ ; Rat ; Electron microscopy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary In the enamel organ of rat incisors macrophages are present in the zone of matrix formation, the transitional zone, the enamel maturation and pigmentation zone. The macrophages accumulate adjacent to redifferentiating amelocytes in the transitional zone. The macrophages phagocytize fragments of disintegrating amelocytes. In addition to the well known complement of organelles the macrophages present an elaborated microtubular system, scattered, thick filaments, a cortical feltwork of thin filaments, and spherical nuclear bodies. The microtubules emanate from “attached” and free pericentriolar satellites and radiate aster-like towards the cell surface or into pseudopods or curve along the nuclear surface for long distances, often related to nuclear constrictions. It is suggested that the microtubular system plays a prominent role in directional movement of the macrophages. The cortical filaments, if contractile, may create the cytoplasmic flow necessary for the cell motility.
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  • 99
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    Cell & tissue research 127 (1972), S. 1-8 
    ISSN: 1432-0878
    Keywords: Parathyroids ; Anurans ; Crystals ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Cytoplasmic and nuclear crystalline inclusions are described in parathyroid secretory cells of adult frogs (Rana temporaria L.) and their possible significance is discussed.
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    Cell & tissue research 127 (1972), S. 323-346 
    ISSN: 1432-0878
    Keywords: Thymus ; Frog ; Development ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A study of the ultrastructure of the developing thymus of the leopard frog (Rana pipiens) revealed that the thymus had undergone all of the major changes which would persist through larval life and metamorphosis by the time that the animals had reached larval stage IV of Taylor and Kollros (1946). These changes included development of an outer, lymphoid cortical region and an inner, essentially nonlymphoid medulla; mitotic activity among lymphoid cell precursors and the formation of the first small lymphocytes; development of complex cysts containing PAS-positive material and the appearance of other signs of secretory activity among epithelial cells of the medulla; and differentiation of large myoid cells containing bundles of striated muscle fibrils. The changes are particularly noteworthy because they first appear during a period in which the animals are known to be developing the capacity to respond immunologically to allografts.
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